There are numerous 404 pages on our site due to the removal of many pages during the redesign, as those pages are no longer relevant. Many of these pages have backlinks from spam sites, and we are unable to request their removal.
The Google Search Console (GSC) report are showing all these pages under 404 issue. We have attempted to validate the fixes in GSC twice, but both attempts were unsuccessful, resulting in "Some fixes failed for Page indexing issues."
Do you have any suggestions on how to address this?