Even if magic gets brought to heel somehow, non-magical characters should get more to do. The vast majority of conditions and basic concepts in the game can be applied to combat using abilities present in real life, and should be available to someone who plans to smash beholders in the face.
Of course they should. The need for Magic to be nerfed into the ground does not imply that non-casters shouldn't have more to them.
Magic has to be nerfed into the ground so that non-casters can then be buffed
up to that level.
Important to remember that DND is still intended to be a blend of sword/sorcery and epic fantasy.
Trying to buff martials to the level of 5e casters (and well beyond them, depending on who you ask) starts to violate the conventions of those genres, whereas nerfing casters to a more reasonable baseline doesn't. DND isn't and shouldn't be about mythic fantasy, and theres way better mechanical structures for that genre than what we have in DND.
To use another game as an example, DCC's magic is oftentimes dramatically more powerful and consequential than that in 5E. Even Wish can seem like a pittance compared to what some spells in DCC can do.
And yet DCC simply doesn't have this problem of a disparity between martials and casters. Part of it is because the martial classes are well designed, but the main reason is because magic is balanced out by how dangerous it is to even try to use it.
DND isn't likely to go that route to balancing what spells can do, so the only option is to nerf it, or accept that the game is going to baloon into a disastrous mess thats impossible to design any further suppments for without breaking the game over and over.