My biggest problem with .NET, is how fast it's moving. Slow down! Also increase LTS support timelines. Default is 3 years, which is just not enough. Ubuntu LTS is the model to follow.
https://dotnet.microsoft.com/en-us/platform/support/policy/d...
We've still got code running on .NET Framework 4.8 (supported, I think?)
We've still got code running on .Net Core 3.1 (now out of support)
We are moving to .NET 6, but given our own 6 month release cycles, and layoffs, I'm not sure we can keep up.