I compiled my first Linux kernel back in the mid 90s, mostly on 386 and Dec Alpha hardware, interesting enough both were not that much slower than what you mentioned, I think the alpha (a measly 21066) took about 40 minutes. If you had asked me back then, I’d probably have imagined a minute or two, 30 years later. Guess it says something about how much larger the Linux kernel has become.

IKEA actually has some but I sort of doubt how much they actually block:

https://www.ikea.com/us/en/p/gunnlaug-sound-absorbing-curtain-white-60500170/