Netlify and Vercel made preview environments a standard part of the workflow for all frontend developers. my usual soundbite on this stuff is we need to treat our envs like cattle, not pets, to make up and discard as casually as a git branch.
i think there are a number of startups (eg Railway, Brev) are all feeling their way towards this future. my one wish is that someone make a credible industry standard for environment branching that everyone can build toward, including 3rd party vendors (eg Planetscale/Neon) and open source multi-service frameworks (eg Temporal, Airbyte where i work).