I'm a sysadmin (or these days "cloud engineer"/"devops person"), and to a large extent I've never cared what the company I work for does.

I like networks, multiple servers, interesting deployments. The actual stuff that is being executed upon those systems is a little interesting, but also a little irrelevant.

There are fields I'd never touch, and technologies which are more interesting to me, but when it comes to looking for a job I'll just google "sysadmin helsinki" and apply to those companies that come top - or to places that friends have recommended.

So honestly? Ordering companies by salary seems like a reasonable enough approach to me.