I've joked once or twice before (over the past few years) that we're coming back, full-circle, to mainframe-style infrastructure with dumb terminals.

Subscription services (even for software on previously steady release cycles), serverless infra, cloud computing, etc... the overall business model is shifting back to buying compute time to perform a certain task, or these startups essentially re-selling general purpose compute time as marked-up specific purpose compute time. With some UI slathered on top to make it look sexy.