Yes, according to cosmology at a large scale the universe is homogeneous and isotropic, i.e. it looks alike in all space directions. As a consequence, no distinguished point in space exists, i.e. no cosmic center.
The statement that the universe started from one point, does not mean that a certain point in space was distinguished as the birth place of our universe. The start of our universe was also the birth of spacetime. One cannot locate this event in a space which existed before.
The above mentioned result about the homogenity and isotropy of our universe does not derive from the Theory of Relativity. Instead, it is a result of observation, mainly of the cosmic microwave background radiation (CMB).
But the most simple solutions of Eintein's field equations from the General Theory of Relativity are homogeneous and isotropic. Hence the observation is in accordance with theory.
Secondly, a deep implication of the Special Theory of Relativity is the relativity of space and time. Both concepts do not have an absolute meaning, only the combined notion spacetime has an absolute meaning. Absolute means that spacetime is independent from the observer and his coordinate frame. While the decomposition of spacetime into space and time depends on the selected coordinate frame - up to a certain degree. As a consequence simultaneouness depends on the observer. Two observers moving with a certain velocity relatively to each other observe different events as simultaneous.
According to my opinion, the latter set of philosophical implications has not yet been fully received by philosophers. See also a previous discussion in this blog Time and space – a subject of metaphysics?