I do miss some of the sounds that let you know machines were doing something - but we also had indication lights, too - mostly gone now, for disk drives. Heck my first laptop had a second LCD to show battery level without the machine even being on.
Many modern laptops still do this though. Dell XPS had some LEDs on the side and a button on the case that when pressed would light up the LEDs as a percentage indicator of battery charge, and my 2 year old Lenovo has this feature built into the motherboard EC controller and Bios that when I press any key on the keyboard when the laptop is OFF, it wakes the laptop's own display to show battery percentage. Modern laptops have many neat features.
Some large OEMs with the resources to do the design effort could use a large passive heatsink on even surprisingly late processor (i. e. Pentium 4) because they could make a holistic design with shrouds and baffles and know you were getting just enough airflow from a case fan elsewhere to keep the CPU within spec.
Early ATX designs, in fact, were often based on "the PSU has its fan placed so that it will draw air over the CPU heatsink and out the back"
Enthusiasts, obviously, went for brute force designs.
It provided some hope that an unresponsive computer was in the middle of a monumental task. Any flicker of light or change on cadence was reassurance that progress was being made and would complete should you wait just a little bit longer.
For kid me, the sound of floppy drives, hard drives, and optical drives were simply mesmerizing to witness. Those were the sounds of the computer performing magic before my eyes and ears.
When I was on call, however, pager storms resulted in the phone being muted quickly. Nothing helps the stress of triaging production issues like the high pitched scream of suppressors and cancellers being disabled.
It's silly at this point in time but windows 3.11 (the first version of windows I used) also feel decidedly "modern" where as DOS is "old" (even though less than 10 years separated my first experiences with them, and both were way longer than 10 years ago).