Not sure whether I understand the question. Are you asking for where the limits are, where the limits should be, where the battle ground between these two actually is?
Also it's not so much about technology itself in that regard but whether or not you are obligated to respect boundaries of other people.
In terms of where the battle ground is, well I'd second @Michael here in arguing it's probably advertisement. Like in totalitarian system the biggest invasion of privacy is probably due to state level actors being in existential dread over the concept of a rebellion. But they most often aim for targeted attacks on specific individuals or groups.
While advertisement currently shifts from broadband to mass individualized surveillance to a degree probably never seen before. Both in the scale and the scope at which that takes place.
Though unlike @Micheal I wouldn't so much focus on the "involuntary nature of advertisement" in the sense of being blunt annoying and in your face. Like that is blunt annoying and in your face, so it's an invasion private spaces, but the much more concerning invasion of privacy is information harvesting.
While often downplayed and belittled as "meta data", this meta data includes a lot more information than people probably are aware of or comfortable telling others. Like your IP alone might give an "attacker" information about your current location even more so if it's the WLAN of a company or organization. So if you use IPs reserved for idk Starbucks and you know the approximate location of the IP (city level or something like that) you can already guess a person's location. Track them over time and you've got information about their habits and whereabouts. Websites track where you're coming from and where you're going to. What you hover over where your focus is rested on all these information are or at least can be tracked. And even anonymization reaches it's limits with this amount of data harvesting because while idk your IP, gender, sex, given name, country your residing, browser and update status, search history and so on might alone not really tell you much about a person, the combination can easily end up being a unique identifier even if you don't save the name.
Like if you ever looked up logarithms or played this lower or higher game you'd know that you only take 30 binary parameters to uniquely identify 1.000.000.000 individuals. You know like if you should guess a number between 0 and 1000 and you always pick the middle number and thus rule out half the available option with each question limiting the number of guesses to 10 or less before you have certainly identified the culprit. The same also applies to data you gather about other people.
But it's not just that you are identifiable and can be tracked in real time, it's also what that information is used for, by whom and how little agency you have in that.
The thing is, the content on the internet is mostly free of charge (discount the ISP costs), partially because not everybody has a profit motive and some just like to share stuff with other people and receive the newest info themselves and that's "profit" enough, partially because they are funded from outside sources like universities and other institutions or because it's commercial and companies want to attract the most viewers to eventually pay for their products or, and that's probably the majority of websites, because they are sponsored by an advertiser or an advertisement network that is also commercial and hopes to attract the most viewers to eventually pay for their products.
Now at first the was a huge boom and lots of companies sponsored lots of websites and every small developer could create their own website and keep the lights on with some banners on the side. But apparently ad companies realized that sponsoring niche communities and broadband advertisement doesn't have the effect that they were aiming for. The internet largely commercialized and nowadays the web is dominated by major companies that unless they sell a service themselves, still generate most of their income through advertisement.
Which leads to the point that "you are not the customer, you are the product". Meaning these websites track your behavior and preferences in order to bundle you up with a bunch of other people in the same category and "sell you" to an advertiser as "targeted advertisement". Ideally you end up actually liking it and buying the products, not so ideally it's large companies using intransparent algorithms to assess who you are and what you want. And even less ideally the point of advertisement has long gone past the point of "showing you products you might like" and is actively in the business of "selling you shit you don't need" or in other words "manipulation". Like if you look at advertisements they don't tell you what their product is or how you use it, they tell you how you should "feel" about it, they're selling a lifestyle and their product is part of that.
And it's not even necessarily as "benign" as predicting your behavior in terms of what you buy. Since the the Cambridge analytica data scandal we know it could also be used for targeted advertisement of political campaigns.
And not just that companies have an interest in keeping people on their website so that they consume more advertisements and buy more shit so they predict user experience and deliberately feed them "stuff they might like". Which ranges from honest recommender systems of stuff you might actually like to rabbit holes of conspiracy theories feeding you a never ending stream of alternate reality interpretations keeping you hooked and emotionally abuse you to keep you watching ads.
And that's not even getting into what an actually totalitarian system or a hacker stealing such a database could do with that amount of individual and collective data. Like Google and Facebook have probably more data available to them than social scientists and thus their ability to analyze but also to make weaponize that data is also beyond the scope of that.
So yeah that about a small glimpse as to domains where the surveillance vs privacy question might be relevant.