I believe everything has to do with the fashion overreaction to mobile. I work in the sector, kinda, and everyone is worried about the gen z coming of age and into expendable income territory, since they're not just digital native but also (almost) mobile centric.
They all moving with breakneck speed to make sure all their branding and sales channel fit with the mobile trend, and logo have some unique issues (like not being responsive) that hamper legibility and would make them feel out of place in a responsive-style website
Open for example rimowa site now on mobile and you'll see the logo fit perfectly with the home other components.
The limiting factor as you say is legibility, but not the logo itself, it's the mobile experience that doesn't allow large style permutation on the design language. The logo here becomes slave of that.