Since you mentioned Zcash and Namecoin, do you have an opinion on ENS, Aztec Protocol, and zkSync? They are trying to solve the similar problems that projects you mentioned do, and somewhat fall into Web3 umbrella.
ENS does aim at the similar problem, but I'm not sure if it's any better than Namecoin. There's this writeup [1] comparing ENS with NMC and Handshake (yet another similar project, with its own chain) and as far as I can tell, ENS doesn't really add anything new to the game, while it has some major inconveniences if you want just the name resolving and nothing else (which seems a pretty realistic scenario to me).
I haven't looked into zkSync or Aztec just yet, but I'm assuming those are dealing with the same problems as Zcash, but on the Ethereum chain? If this means you can just throw in some generic ERC-20 token and get a zero-knowledge version of it (like what z-address is to t-addresses in Zcash), that's pretty cool.
