Something to also consider is how many skilled carpenters, maintenance workers, etc. have retired or were let go from their respective industries because of the pandemic, and as a result have also taken decades worth of institutional knowledge with them. Knowledge that will take the less-experienced workers who are now in these roles years or even decades to gain and build back up. That's also in addition to however many smaller companies who are now out of business that previously manufactured highly-specialized replacement parts for these rides. While those are no excuses to operate rides anyway if they are deemed unsafe, I'd speculate that keeping these rides running in the shape they once were is probably the most difficult it's been in a long time.