The sync over async issue is a real common problem for me when trying to get a large older codebase converted to async and you can't just do it all at once.
You still need support non async callers and you want to share code between the new async version and the old sync versions it makes it really difficult to do so.
Say you have a db layer you want to move to async but you still have to support a sync api over that, no great way to do it without hitting the potential issues, instead you have to have two versions in the db layer with no great way to share code.
What worse is when you don't even have the option to go async for instance if your not on .Net core but Framework 4.8 with the latest version of ASP MVC there is no ExecuteResultAsync on a action result so you really can't call any async code there safely, they added it to MVC core later.
Bottom line sometimes you're at the mercy of your callers and not being able to easily expose a sync version of your api when needed without a bunch of code duplication is a real problem that I have hit. I really think they should have spent more time in the beginning to allow that scenario without pitfalls and the transition would have been much smoother.
You still need support non async callers and you want to share code between the new async version and the old sync versions it makes it really difficult to do so.
Say you have a db layer you want to move to async but you still have to support a sync api over that, no great way to do it without hitting the potential issues, instead you have to have two versions in the db layer with no great way to share code.
What worse is when you don't even have the option to go async for instance if your not on .Net core but Framework 4.8 with the latest version of ASP MVC there is no ExecuteResultAsync on a action result so you really can't call any async code there safely, they added it to MVC core later.
Bottom line sometimes you're at the mercy of your callers and not being able to easily expose a sync version of your api when needed without a bunch of code duplication is a real problem that I have hit. I really think they should have spent more time in the beginning to allow that scenario without pitfalls and the transition would have been much smoother.