Is the internet a commodity in the Marxist sense?
It may help to know if it's made, bought and sold. Can people own more or less of the internet, and in what ways?
The simplest definition of a commodity consistent with Marx is that it is anything produced for market exchange.
Internet access is clearly a commodity in that sense. You pay for it. Even when you get free WiFi, the provider is paying someone else for it. Access to the Internet is produced through the installation, configuration and maintenance of infrastructure like cables, routers, etc. In turn, this production of the Internet is itself overwhelmingly organized through commodity exchange.
But on the other hand the Internet as a whole is something more complex and infrastructural. Much of what takes place on the Internet (the circulation of cat memes, for example, or our participation on this forum) has nothing directly to do with commodity exchange. The Internet has become a basic feature of capitalist society, and is closely tied to the circulation of commodities in many different ways (advertising, e-commerce, financial markets, etc.). But it would also be a meaningless over-simiplification to describe "the Internet" (in itself as a totality) as "a commodity". It is much more than that.
On this point, it is perhaps a helpful comparison on this last point would be to Marx's views of the state. The capitalist state is essential to the production of commodities. It may even produce commodities directly. But it is not, in and of itself, a commodity.
Or to put it a bit differently, we might say that the Internet is implicated both in the base and in the superctructure of capitalist society today.
Good question - and a little complex.
The Internet was originally envisioned as a democratic/"open source" platform where people could freely exchange information and ideas.
However, it has been largely commercialized, and powerful entities like the U.S. government and Google also use it as a means of surveillance and extracting a vast range of personal information about millions, if not billions, of people.
The Internet has further become a major propaganda platform, similar to the traditional media. Much of this propaganda and surveillance can be seen in the so-called social media (e.g. Facebook).
I'm not sure if the Internet can be literally owned, but it can certainly be controlled. Websites like Facebook, Google and YouTube have become online vacuum cleaners that use a wide array of technological gimmicks (and some old-fashioned ones) to lure people to their platforms.
Google also has the power to obscure or even block websites they don't like from their search rankings. So there's no question that the Internet can be controlled, if not literally owned.
I believe Facebook and Google are both banned in China (and probably a few other countries), while some countries may ban the Internet in general.
Making things still more confusing is the question what constitutes "The Internet"?
Does it include the so-called dark web, that portion of the Internet invisible to traditional search engines and browsers?
And what about Internets created and controlled by various countries? I don't even know if any such internets even exist, but I believe Brazil was once talking about creating their own Internet.
In summary, I can't answer your question. However, it can easily be demonstrated that the Internet is a complex thing combining a free exchange of information with commerce, government/corporate surveillance, propaganda and a lot of high-tech manipulation and bullying.
I'm going to go out on a limb and speculate that Marx would have coined a special term to describe it. ;)
It strikes me that the internet as such is (a) a platform for distribution of informational commodities; (b) a sphere of productivity for these informational commodities; (c) a sphere of consumption of informational commodities; and increasingly (d) a zone of circulatory exchange for digital labor (i.e., directly trading currency for applications of informational skill endowments) or even as (e) a global workspace for serving virtual “meta-economic” values (I.e., currency or tokens exchangeable on demand for abstract informational capacities).
Clearly people own these platforms, and profit from them. So there is a kind of virtual rent extraction for sure. More broadly maybe the internet is a kind of abstract territory where all the strata of existence combine; for instance the broad extension of the state into cyberspace is one particularly relevant contemporary instance of profound mutations occurring in the order of the world, driven by hyper-connectivity. The internet is effectively the abstract machine on which global informational capital processes its programs, and through which the states extend their contention and desire for control of their subjects ever more “immanently”, ever increasing the transparency of the intimate flows of information in which all of our lives have been enmeshed.