Kinda funny to call the current 90 day certs "long lived". When Let's Encrypted started out more than 10 years ago most certs from major vendors had a 1 year life span. Let's Encrypt was (one of) the first to use drastically shorter life spans, hence all the ACME automation effort.
To someone like me with hobby-level serving needs, the 90 day certificate life is pretty inconvenient, despite having automation set up. I run a tiny VPS that hosts basic household stuff like e-mail and a few tiny web sites for people, and letsencrypt/certbot automation around certificate renewal is the only thing that I seem to need to regularly babysit and log in to manually run/fix. Everything else just hums along, but I know it's been 90 days because I suddenly can't connect to my E-mail or one of the web virtual hosts went down again. And sure enough, I just need to run certbot renew manually or restart lighttpd or whatever.