> Hell I just replaced thousands of older desktops with slower laptop chips — nobody noticed.

This is certainly plausible if these were mostly Office users but how confident are you that you'd know if they did notice? Most of the large IT departments I've interacted with would post glowing self-evaluations while the users had plenty of complaints and/or were doing their real work on personal devices. Depending on how the business is structured and the relationships, this can be hard to measure without a fair amount of effort — I've heard people say they weren't going to report something because they didn't think it was worth the effort or they were sure that the IT people would notice and fix it.