I blame Microsoft for that

And COBAL COBOL just won't die.

As backend code, yes. As a web (web, not api. As an api platform they're great) platform... No.
Asp.net and mvc were imo a disaster, silverlight was... Oof.
Then there is maui which could have done it using blazor but just... Didnt.
... And then there is blazor itself. Though blazor is imo the best of all the web platforms they had, and i like it, it still has very rough edges and is not gonna replace javascript any time soon.
Hell, microsoft cant even decently support their own web ui platform ( fluentui ) because their backbone ( webcomponents ) is completely broke ( or did v3 FINALLY release? ). There are other blazor frameworks but they all seem to not take full advantage of blazor and its disgusting.