Sorry I should have been more clear on this (also sorry for the late response, I was on vacation). This only applies to the Strapi packages, IE packages that we the Strapi team maintain (not community packages). The reason for this is when we release an update, all of our packages get updated regardless of any changed code or not.
It’s intended that all of the official Strapi packages are the same version, and trying to mix and match will almost certainly cause issues. Due to the “messed up” way npm can work sometimes due to mirror latency, ect. It’s not uncommon that one package may show a higher version when resolving the various ^, ~, <, > options.
You should updated based on the migration guides themselves, if we have a guide to from 3.4.x to 3.5.x then you are good to jump that far but if we have a guide from 3.4.3 to 3.4.4 you should follow it. In the case of no migration guides between your current version and the latest you can jump straight to that latest version.
We don’t follow semver “to the letter” yet, but we plan to in the future. It’s just been crazy busy and we have a bunch of refactoring that will happen later this year in v4.
Everything should still work, however any bugs you find and create bug reports for need to be validated on the latest version (see the contributing guide on the monorepo for more info about this). We generally only “support” the current latest minor release aka 3.5.x as of writing.