> externalized to your users

You mean if you have customers with less powerful devices like the OP? I don't really see internal services or B2B products having that problem.

You original point

> the Javascript ecosystem is unmatched when it comes to very quickly creating frontend applications

Didn't hinge on whether you were creating internal tools or not. You simply used internal tools as an example of what you personally do with JS.

I see your point, and I agree it's definitely not a good solution to some problems. But I think it can be very productive if your constraints allow you to use it.

That would be fine if the attitude were 'best tool for the job'...

Often there is the people element to tech though - that isn't the attitude, normally optics is your tech wiz kid is doing something cool with (metaphor) peanut butter sandwiches, lets build our next office complex with peanut butter sandwiches. Architecture? What's that. Move fast, break things, eat lots of sandwiches.