Earlier quoted context omitted.
Ok first thing first - allow me to vent my existential frustration with few off the cuff (mostly rhetorical) questions ... You call decade a substantial longevity? Is this some kind of a joke? Is your ability to assess being held hostage by js ecosystem expererience? But seriously - I expect a bit more from platform that could potentially waste my life and my venture. I am still happily supporting some Java (and JSF)…
The difference is that Blazor is built on web standards (WebAssembly), not a proprietary technology. Sure, Microsoft could discontinue support for Blazor, but WebAssembly will keep running. C#/Blazor are not the only technologies using WebAssembly. I personally wouldn't use Blazor for a public facing website, and would only use it for an internal LOB app where I know I can dictate what browser technologies can be use…
Silverlight came when flash was being dismantled shortly after.
Different days back then.