So now you can spend ~$150 for the first time ever in that machine's life and get 10.4 on it.
Actually not even that much, you can buy a copy of Tiger on eBay $50 or less. The grandparent is trolling for shits and giggles, so no point in trying to refute him.
The clones were poorly made and executed the old Mac OS rather poorly. This hurt Apple's overall reputation.
I don't think Apple's biggest problem with the Mac clones of the mid '90s was the tarnished reputation of Mac OS. A much, much bigger problem was something that you also point out in your comment - most people chose cheaper, not better. The prices of the clones did severely undercut the prices of "genuine" Macs and as result Apple's sales practically disappeared. And you are correct - the same would happen today, too.
It is much harder to find a job than to keep one.