True, but then the alternative is usually that the disparity between skill levels become so great at high levels that the less skilled have no hope to hit the DCs while the highly-skilled almost can't fail. Thus, gameplay contracts as everyone is increasingly siloed into their specialties. That appears to be the case for 5E's saving throw system with many high-level characters and CR monsters having a couple of abysmal saves that are basically auto-fails.
Is that actually necessarily a large problem?
PF2e, for instance, takes this path for
some checks. At high levels, there's a potentially tremendous gap between somebody with no proficiency at all ( just the relevant attribute modifier ) and the basic 'Trained' proficiency ( granting an additional 2
plus level, where PF2e also has a level cap of 20), larger for expert/master/legendary proficiency (+2 per tier). However, everybody gets at least 'Trained' proficiency in all three saving throw categories, unarmed combat, and unarmored defense; and even characters who aren't in "skill monkey" classes get a pretty generous number of skill increases ( one every odd-numbered level ) which they could use to get 'Trained' in quite a few (particularly given that one cannot use the skill increases to reach master or legendary proficiency before levels 7 or 15 respectively). For perspective, there are sixteen 'normal' skills in PF2e, plus the 'Lore' category; outside of specialized knowledge represented by Lore, it's not a super-granular system and one could indeed be pretty versatile.
In that system -- ordinary, "normal" challenges like scaling a wall, trying to stabilize a downed creature, or repairing a damaged shield don't have scaling DC; one doesn't need to be an expert in them, while experts basically auto-succeed (and in some cases, can find it worth it to try higher-difficulty variations, such as a higher-challenge + more-rewarding version of Treat Wounds).
And then there are extraordinary tasks for experts. Trying to "Earn an Income" by acting as a defense attorney for clients in Hell is explicitly a Legendary difficulty task, as is running an international brewing franchise. Armor and weapon proficiency is also included in the level-based scaling, so an oblivious brigand trying to attack an unassuming middle-aged man who happens to be a retired high-level monk is also going to have an extremely bad time of it. High-level challenges of such nature require at least some training to have a meaningful chance of success, but that strikes me as reasonable.