I'm still trying to wrap my head around the thermometer shortage - did people not have thermometers at all before this? Or is there some reason to hoard them? It's not like these things are consumable or break easily.

You might be able to find some on Amazon that are... marketed somewhat specifically but still work well for general purposes:

https://www.amazon.com/Digital-Basal-Body-Thermometer-Temperature/dp/B07ZRL44D1