I think it's clear to people who specialize in that. I don't know why startups don't hire a DevOps/SRE/Syseng/Sysadmin/Architect contractor right off the bat. Hire a really experienced one for one month and they'll give you several different options, lay out the pros and cons, costs, staffing, time estimates. Take their suggestions and implement the one that fits your business plans.
For example, a single VM you ssh into works fine if you do daily VM snapshots and deploy from snapshot. If somebody breaks it, revert to last working snapshot. Blue/green in multiple environments work with it too. Super cheap, super simple, easy to recover, automated. Very boring.
> I don't know why startups don't hire a DevOps/SRE/Syseng/Sysadmin/Architect contractor right off the bat.
It's entirely likely that they are doing this, but the DevOps/SREs that they're hiring are prescribing the tools that they know and have seen work in the organizations that they're coming from.
I've been an SRE for nearly a decade, and I honestly couldn't tell you in detail how to set up a pet-VM deployment with automation and guidance about who deploys to it, on what cadence, etc or who operates it, etc. In my first DevOps job, we were doing something like this, but it was a hot mess--that startup hired the wrong sysadmin to bootstrap us, and the next guy they hired moved us to AWS ECS (running on Fargate) and that was a dramatically more effective solution for us. The point isn't that ECS > pet VMs, but only that we were able to find a successful path with ECS where we were unable to with pet VMs despite hiring someone who allegedly had that experience. For that organization, ECS (rather than pet VMs) was the Very Boring Solution (mind you, I'm not a particularly big fan of ECS either).
For example, a single VM you ssh into works fine if you do daily VM snapshots and deploy from snapshot. If somebody breaks it, revert to last working snapshot. Blue/green in multiple environments work with it too. Super cheap, super simple, easy to recover, automated. Very boring.