Chaosmancer
Legend
I don't think that kind of worldbuilding critique is a unique weakness of moving supernatural effects to skills. There's plenty of stuff in the magic system, even if we don't adjust how it functions, that threatens the fabric of a campaign setting if we start thinking through prices and "what if there was actually a couple of court wizards?"
Don't get me wrong, I'd love some more time spent on the economic and social implications of the abilities in the PHB and yeah, a society with mass teleportation regularly available to the upper and middle classes is a very interesting conceit I'd be happy to build on. I don't know if that's a particularly relevant argument for whether that's something non-magical characters should be able to interact with.
Unless, and it's possible I'm missing some context here, this thread is long, you're proposing that this kind of utility needs to be separated from the skill system, which needs to model universal mundane capability, and moved instead into class features?
I'm not pointing it out as a weakness, more as a... I'm not sure how to explain it.
The prompt from the OP was how to remove magical dependency for high level martials. This idea works... but it works equally well for low-level martials. It is a world-building solution that simply states "this high level magic instead becomes mundane and common" In the same way, you could remove the need for high level mages to create planar portals by having massive, well-known planar crystals that allow anyone who touches them to transport themselves to another plane of existence. With this a high level martial doesn't need a spellcaster to travel the planes.... but neither does the level 1 potato farmer.
I'm not saying they are bad solutions per se, just that they are less "solutions for powerful martial warriors" and more "solutions for world-building high level magic into every day existence". It becomes a world-building exercise, not an exercise of the classes.