That is made up reason. Extension periods depend on TLD providers. I've just checked and e.g. OVH lets me renew .com domain until 2030. You max our renewal now, then setup some "domains housekeeping" day in your yearly calendar to puth the expiration date every year. Pity I can't do that with some proven and basic hosting to prepaid a few years ahead.

The reasoning might well be valid in general, but only you can decide whether it's applicable to you or not.

FWIW, name.com lets me renew my domain for 10 years at a time, so it's definitely not something that all registrars do.

> My register doesn’t allow registrations longer than 1 year.

Ummm.. then maybe get a better registar? It's not like there aren't many to choose from.

I think you missed the last part of my comment.