In general, I'd go for what is most common in the company or what the team is most familiar with. There are a lot of great frameworks out there and each languages has its merits and its PITAs...
Hypothetically, if I had to develop a "highly used API" and given the chance to decide on everything and assemble my team accordingly, I would probably go for Rust, because it's an awesome language, very stable and very innovative in the right places. For the framework, I would probably go with actix. It is easy to use and the fastest web framework out there. Alternatively, I might consider Rocket, as it feels similar to Spring (not saying that Spring is good, but it's kind of standard).
At the same time, hypothetically, if I had to develop a "less used API" and given the chance to decide on everything and assemble my team accordingly, my choice would definitely be TypeScript. About every cloud provider and their dog provide some kind of NodeJS hosting. All web devs know at least JS, and TS is the better alternative. The only issue is performance and costs. Anything JS is inherently bad at it and while scaling is possible, costs quickly skyrocket compared to alternatives. On the upside, everyone knows JS and it's very easy to kickstart a project. For the framework, I'd use either Express or Loopback, probably double-checking professional support options for both.
The industry-alternative would be to go Java with Spring. Most big companies I know about are looking for Spring devs, so you can't really go wrong with it.