Will the placement of casters on speaker stands degrade the performance

in theory yes, in practicality it depends...

on the speaker
on the room
on the type of stand and caster mechanism (locking non locking, swiveling, connection hardware)
on how much work you put into leveling and positioning
... and mostly, can you actually hear the difference...

then again, they do have their benefits too...

To answer OP, yes!

@twoleftears’ suggestion is a good one. Use the Herbies until you find your permanent (ha!) speaker placement, then if you want remove them and install the footers of your choice. You can try the current rage---springs---without (heh) springing for the Townshend Seismic products. If you like what they do, start saving for the latter!

By the way, if you think moving around the 3.7i is hard, try a Tympani 3-panel model! Grant Mye makes a stand for the Tympani's, but they're not cheap.

Sure, there will be the question of stability with the large-frame speakers, there will be an acoustic effect as the speakers are lifted slightly higher above the floor, and MC's statement about problems with precise positioning on carpet is true enough. My opinion is that the positioning knowledge OP gains will more than offset those issues.

At the end of the day, I wager OP will have moved his speakers around more than many listeners who experiment with position and orientation. OP will be able to dial them in for his room, source, electronics, music preference, and so on. OP is tweaking and evaluating, and that's what the quest is about.

The only reasonable solution is to dampen the floor with water, freeze it, and attach ice skates to your speakers.