My Mac hangs from time to time where I need to do a hard shutdown. So it may be a modern machine but the OS still has bugs. I don't know of any complex software that doesn't have bugs.
I think that shutting down devices periodically does help. It could be a VM leak (I always hate debugging those) or a structure limit. I do have to reboot my iPhone from time to time. I had to reboot my iPhone regularly for a few months. I determined that it was when driving in a certain area - my guess is that it was a bug with frequencies or something. It was fixed with either a carrier update or an iOS update.
I just recently got a 2019 15 inch MacBook Pro and I've noticed that it drains the battery a lot in sleep mode. Nowadays, I shut down my MacBook at night and now it doesn't drain my battery. I don't have any apps open either, but my battery drains a lot in sleep mode. It's worrisome.