I bought 4 of the same tablet (Fire HD 10) on Black Friday 2021 for Home Assistant dashboards and a Fire HD 10 Pro (edit: actually Plus) I use as an E-reader/browser (with KOReader/Firefox). To save money I got the cheaper version with lockscreen ads pre-installed but before ever letting them online I ran Fire Toolbox to remove the ads, debloat, block updating and install Google services. Fire Toolbox is excellent: https://xdaforums.com/t/windows-linux-tool-fire-toolbox-v45-...
I've never had the problems OP describes but my tablets all came with FireOS v7.3.2.1 and I've never let them update. I think Amazon started locking down later firmware versions more but Fire Toolbox can still do quite a bit to tame and decruft later versions. The XDA forum for Fire Toolbox has a lot of posts covering exploits and workarounds for later FireOS versions.
Once the Amazon cruft is tamed, I still haven't found a meaningfully better 10-inch thin/light Android tablet than the 2021 Fire HD 10 Pro. It has wireless charging, weighs 430g and at 247 x 166 x 9.2 mm no one makes a 10" that's much lighter, smaller or thinner. The only slight downside is FireOS 7 is based on Android 9 and new versions of a few apps are starting to require later APIs. I'd gladly pay ~$250 for a 10" Android 16 tablet with wireless charging that was as thin & light but had smaller bezels for overall smaller size.
I've never had the problems OP describes but my tablets all came with FireOS v7.3.2.1 and I've never let them update. I think Amazon started locking down later firmware versions more but Fire Toolbox can still do quite a bit to tame and decruft later versions. The XDA forum for Fire Toolbox has a lot of posts covering exploits and workarounds for later FireOS versions.
Once the Amazon cruft is tamed, I still haven't found a meaningfully better 10-inch thin/light Android tablet than the 2021 Fire HD 10 Pro. It has wireless charging, weighs 430g and at 247 x 166 x 9.2 mm no one makes a 10" that's much lighter, smaller or thinner. The only slight downside is FireOS 7 is based on Android 9 and new versions of a few apps are starting to require later APIs. I'd gladly pay ~$250 for a 10" Android 16 tablet with wireless charging that was as thin & light but had smaller bezels for overall smaller size.