In that sense you are right although it was not so legally. And the Russian hegemony happened more by default then by intent. I do not think Lenin got together with a bunch of Russian nationalists and said- "I have a plan, let's change the name of the country and then we would keep the Empire". No patriotic Russian would ever do that. But what language would they use? Make all people speak Georgian? Impractical. It is like making all people in the British Empire speak Hindi or Urdu. Teach all science and engineering and medical courses at higher institutions in local languages? How would all these nationalities communicate this knowledge, read directives, use technology if it was all in local languages? How could they go and work in other parts of the USSR and what common language would they use?So Russian language and unspoken cultural preeminence was the reason I considered the USSR to be the Russian Empire. With your input in mind, I would call it "a" Russian empire cloaked under the guise of ideological equality of Soviet nationalities.
So, sure after that the Russian majority came up on top plus they were better prepared, better educated and with more industrial experience. But still.
Look at who was at the helm, though, at least in the beginning. Many Jews and other non Russians /non Slavs. It was not allowed when the country was called Russian Empire.
Also, where would one put the capital? In Kazakhstan? Would make sense geographically except that the infrastructure was not there. The money was not there to build a capital, either.
I can also say that I consider the British Commonwealth of Nations or Great Britain itself as basically, the English Empire. And even the US falls into that. The English language, the foundation of the country is based on English values, English common sense. That is why it is called the Anglosphere, not a Brito-sphere.
The English people as a rule do not bother to learn Gaelic languages when they move to Wales or Scotland or to fit into the local cultures and even learn the brogue or let alone learn Singhalese, Chinese or Malay if they move to Sri Lanka, HK or Malaysia. They still think they own the place.
So, yes, all the Anglosphere may seem to be an English Empire, too. Not all will agree with it, though.
Come to think of it, we all have a right to our opinion and what we consider things to be, people to be or places to be. And we may be right factually and from our perspective. What things, places or people are legally on their territory and according to their laws is a whole different thing. And what they call themselves is another story , as well.