One of the problems is there's only a small certain percentage of scenarios/applications that benefit from very short start times.

I'd wager most of the services running on the interwebs are web servers, database servers, inference servers etc that don't change over their lifetime really. They're just doing the same thing all day long every day.

If you're doing stuff like what I'm doing for work right now, which is, yeah, multiplexing potentially oodles of user-submitted jobs, and those jobs are best expressed as distinct images or containers, then yes, managing start times is absolutely imperative in improving utilization/occupancy and therefore reducing costs.

But I'm not convinced that's a typical scenario, not typical enough to drive enough time and money investment in this space maybe?

Also there ain't currently no real "hypervisor" for the (NVIDIA) GPU. Not practically anyways. And that's arguably where we need it the most. Or at least I do, for Day Job(tm).

So unikernels and microvms may have to lean on other arguments for adoption: security and simplicity-to-reason-about might be those...