Here’s a simple one: corporate policy doesn’t allow you to send company data to a cloud service. There are a ton of people with significant budgets in that situation.
I think that use case still matches the remote cluster use case better as a policy like "We can't use cloud" doesn't mean "we have to use our individual local workstations". This approach really makes sense for the "we have 1-3 people that want to really push this on a budget", beyond that big iron makes more sense. And this still helps with that IMO, it's just one step in getting to there from "only the largest can play".
Maybe, but that’s potentially slower and definitely much more expensive. A lot of people in those environments can get a $6k workstation a lot faster than a compute cluster which has to be supported, secured, etc.