I had a late 2007 iMac fail in 2014. The power supply blew, and fried the logic board. Most of my backups were in Time Machine. Non-recoverable failure.
Funny thing about Time Machine, I discovered. The only computer that can recover backups in Time Machine is the computer that made them.
Fortunately, I had stored things like my photo files on other hard drives.
You can restore to a Mac running the same OS level, but in it does not require the same computer. There are ways of restoring even with a different OS level. But they require jumping through some hoops. I always thought it was stupid to link it to the OS level.
That is not my experience. Last time I upgraded MacBook Pro machines, I used the TimeMachine backup from my old one to “restore from Time Machine”.