After reviving a PC i had in the late 90s a couple of weeks ago i investigated this big box of CD-Rs standing besides it (in an unisolated attic in germany... so temperatures from about -5 °C to >35 °C), most of the CDs were burnt in a period from around '96 - 2005, many ... ehm... "off site backups" of games and other software but also personal files.
What can i say... every CD i put in the drive worked flawlessly. I think it sometimes comes down to pure dumb luck.
Quality can vary a lot, back in the late 90's you had certain brands and disc you would buy because of how much extra data you could write to them and also testing to see which disc performed better at higher writing speeds. It was a big deal to some folks back then and you likely bought the high quality ones.
What can i say... every CD i put in the drive worked flawlessly. I think it sometimes comes down to pure dumb luck.