Those keys already have their own layers in a lot of software. Having to press yet another additional modifier key destroys usability and muscle memory.
For me it’s the opposite: I get RSI from having to stretch my hands to press 2-3 modifiers simultaneously, whereas moving my hands a bit is no problem.
If there are different preferences for arrangement of keyboard layout, then my vote goes to: it would be amazing if there were a laptop where such things could be customized.
Then the people who want niche 40% or 36-key layouts can go with that, and those who prefer more keys can go with that.
IMO, the row-stagger is an unergonomic, archaic skeuomorphism. This is also a niche opinion.
Unfortunately, I'm sure there are practical reasons why "modular keyboard" can't happen (not enough market interest, strength of the laptop hull suffers if the keyboard is a separate module, laptop couldn't be as thin, etc.).
I'm far more comfortable moving my fingers and thumbs as little as possible rather than having to stretch far and wide for those extra function keys.