My personal experience has been surprisingly good even with cheap TDK CDRs I burned in the 90s still reading just fine decades later.

For especially valuable data you want to preserve for 100+ years, there are "archival quality" discs [0] [1].

[0] http://mam-a-store.com/goldcdr.html

[1] https://www.mediasupply.com/mamgold.html