But cloud or not, if you setup a private network with v6 you can get a nice /48 prefix, and you give out /64 prefixes to VMs, so you'll have 48 unchanging bits to memorize (or put it into a .txt to have it near). And most of that will probably be zero anyway.

For example 2a00:1450:4001 is a /48, and 2a00:1450:4001:082b /64. Only change is "082b".

I know, it's not the same as just remembering 1.1.1.1, but most of the people working with v4 never had so simple addresses to work with. (And if we're talking about 10.0.0.0/8 and other private addresses, well, folks can continue to use them, if they want to endlessly debug NAT and static routing hacks.)