Don't bother with specific tech stacks, because as mentioned, the churn rate is really high. Instead, hire good problem solvers who you can tell from their interviews will be able to choose a framework that works well for your new projects, or adapt to the framework you've chosen yourself for your existing ones.
Understand that good programmers are kind of hard to find, but okay programmers with experience in XYZ stack are not. Why? Because any reasonably competent programmer can become familiar with a new framework or library in about a week or two. Being able to separate the signal from the noise, and architecture an application well within that framework? That's what you're looking for. The tools themselves aren't that important.
Of course, to follow this advice you have to be able to identify problem-solving ability, which is hard and why most hiring managers fall back on buzzword bingo--to say nothing of HR departments.
Understand that good programmers are kind of hard to find, but okay programmers with experience in XYZ stack are not. Why? Because any reasonably competent programmer can become familiar with a new framework or library in about a week or two. Being able to separate the signal from the noise, and architecture an application well within that framework? That's what you're looking for. The tools themselves aren't that important.