I would say yes and no. It is a game about evolution with some similarities but it is very focused on a realistic representation of evolution. This makes it a more complex game than spore and actively encourages many different niches not just agressive, peaceful and mixed as spore did.
Aldo currently they are working on finishong the cell stage and the beginning of the multicellular stage while have more in deapth discussion about the transition between the microscopic and macroscopic phases among other things.
From a quick video I saw, they seem similar indeed, but I haven't played Thrive enough. I have only made it to a single-cell prokaryotic organism, lol (which is basically very close to the beginning of the game).