Thomas Shey
Legend
A high level challenge must take in to account things like "the PCs cannot be stopped by locked doors" and "the athletic one can spiderman climb on ceilings" and so forth. There's a general understanding about PC capability as it relates to spells, we understand PCs can deploy flight and teleportation and scrying and all that, but we tend to try and make the skill game exactly the same; instead PC capability actually needs to expand, thus that they have different tools to resolve problems. It's insufficient to simple change the adjectives describing the challenge, it's underlying structure needs to change.
Of course that can end up feeling like the rogue is just a necessary ritual component (in the sense if they're there, the locked door is not an issue, but they don't really do anything).
I mean, yes, sometimes mages work that way, but mage players are also used to have a wider range of things they do, and a lot of what they do being all or nothing. Non-spellcasting classes are not similarly versatile, and if what they do is solve problems by fiat it can end up feeling to players of same that they're just effectively a piece of equipment.
So I don't really think that "above a certain point, locks are never a problem again" is actually going to be a satisfactory solution to most people.