I'm not certain what point you are attempting to make, The size of Windows install has not smaller and therefore improving install time, but rather the hardware has gotten so much faster. Installing from a USB 3 key is so much faster than floppy or optical media, as well as NVMe drives are receiving the data vs old spinning rust drives.
You can find complaints about Windows Vista, but then find praise around Windows 7. Being better than a single point in the past doesn't imply a trend. The perceived quality varies between releases, and it's clear that Windows 11 has dipped in that regard.
Even windows 7 had complaints when released but it kept improving, on the other hand windows 11 is deteriorating in both stability and anything new added is either half baked or unnecessary borderline user hostile.
If for example you take a bus to work, and starting this month, the bus shows up only every hour (last year it was every 10 minutes), would you be frustrated?
But if you complained about this and someone said "Well in the 90's this bus showed up only every 4 hours!"...
Reinstalling Windows used to take an entire afternoon. Now I can do it in an hour.
Basically Windows and computers in general have always been frustrating.