I own a 3-letter domain with a 2-letter TLD and still spells my family name. Many of my friends finds it cool when I share links via that domain. The links are indeed easy to remember but it comes at a higher yearly cost of renewal and I had forgotten to renew twice. Luckily, I was able to re-register them (nobody wants it, ;-)). Example https://oin.am/rr/
I sign up for accounts with emails like apple@corl.in and that lets me easily filter and organize my inbox.
But when I have to tell some customer service rep my email they get very confused.