I wouldn't call Paxos on the decline. It has several nice properties that Raft lacks[1]. However, implementing it correctly is more brutal than Raft, which is cut into easier-to-understand components.
Also, the paper introducing Paxos[2] is famously obfuscated, while the Raft website[3] trivializes the problem, and has ready-to-use libraries.
As a result, there are more recently-developed systems in Raft than Paxos, but I expect there is more volume hitting Paxos systems than Raft ones in the world.
[1]: http://rystsov.info/2017/02/15/simple-consensus.html
[2]: https://lamport.azurewebsites.net/pubs/lamport-paxos.pdf