This has been my go-to training approach for decades. Many of those individuals are now in high-seniority roles that encompasses Linux Administration.
It is a tried and true method. If you want to be _good_ with Linux (including administration), build it: Follow the Gentoo Handbook, and restart every time something is wrong or fails.
Alternatively, if you want to be a semi-competent user you can go the path of installing a user-friendly distribution (like Ubuntu, etc.) and get various Windows-based workstreams working (Gaming, Windows-Only Software through Wine, etc.) But this is less likely to push you to the same tier.
Gentoo handbook method is a lot friendlier than following LFS, yet you stil have to deal somewhat with linux internals. IMO the main advantage over LFS is that is close enough to day to day linux administration that it serves more as a real experience than LFS which seems more like an academic experiment.
OTOH, watching stuff compile is the worst part. I would complement the experience with using something like arch for a few weeks as main driver. Quicker than watch compilation logs, still you have to deal enough with linux internals.
It is a tried and true method. If you want to be _good_ with Linux (including administration), build it: Follow the Gentoo Handbook, and restart every time something is wrong or fails.
Alternatively, if you want to be a semi-competent user you can go the path of installing a user-friendly distribution (like Ubuntu, etc.) and get various Windows-based workstreams working (Gaming, Windows-Only Software through Wine, etc.) But this is less likely to push you to the same tier.