I cannot speak to the whole industry as I moved to the states a year ago and my view is quite limited. But for sure Node has a lot of traction and usage in here.

However, generally, I feel developers live in their own echo chambers. For example I personally am very much connected to JS people and Linux/Open Source people. I rarely meet any ASP or Java based stacks.

I think it also depends on who you are developing for. Governments and enterprises for sure use more Microsoft or Java based solutions while startups and private companies are more "bleeding edge".

So to answer your question, I think you're right. If an organization is using WebForms, their most probable choice for upgrade is the newest offering by Microsoft. That's where they have already invested it. collectively.

But other stacks have a lot of users too. And they are not going to switch to .NET even if it becomes FullStack.

This Google Trends results [0] are interesting. Not sure if they tell us anything meaningful or not though.

[0] https://trends.google.com/trends/explore?date=all&geo=US&q=....