I guess it comes down to the stakes for failure. Something I tell new DM's a lot is "if you don't want something to happen, don't make it dependent on a die roll". You see this in (bad) adventure design "to get through this door that leads to the rest of the adventure, a DC 20 Dexterity (Thieve's Tools) check must be made", and of course, odds are the players fail. Now what?
There's a lot of things you don't really want to be a coin flip, but many DM's feel that dice must be thrown for most any task, and they seem to have a phobia of making things easy for the players, lol.
If the stakes for failure are no big deal (there's an alternate route, you can find a key, etc.), it doesn't matter if the DC is a little hard to hit, especially if you can try multiple times and maybe you can use Help or Guidance or Bardic Inspiration (or just regular Inspiration). Easy peasy.
However, if the check is rather vital to proceed in an adventure, or can lead to serious pain and injury, and you can't set up the ideal situation for it, then things become a bit fuzzy and potentially problematic.
Hopefully the 2024 DMG will actually give new DM's more insight into when to ask for checks, and what reasonable difficulties are (I'm not a fan of +5 DC ascending myself, since most characters only improve their checks sporadically, if at all, meaning it can be quite some time before you can make DC 15 checks as easily as you could make DC 10 ones when starting out. I mean, imagine if AC went up by 5 per Tier!), and to always have a backup plan (or some way for players to "fail forward" so as to not bring the game to a screeching halt because of failed checks).