Currently on J4 for most of my website, I had one in Joomla 5 for fun this summer... Well it was no fun at all... The main problem is some of the extensions are either outdated or no longer updated, so you might have to uninstall them and find something that is supported in Joomla 5, and that is not always possible.
For example a simple visitor counter, it took me 3 weeks to find a suitable replacement for Coala Web Traffic counter (J3) to install on an updated version of the website I was migrating to J4 and J5.
But J4 works like a charm and my customers are not to demanding, this summer I'll upgrade some of my older customers to J5 if most of the extensions follow the version. I guess its a waiting game.