I think it could be better titled "Don't Become an Academic Professional or Professional Scientist." They have good reasons for this. Whereas, you can do science as a hobby in your spare time for free or up to your chosen budget. You can publish whatever you want on your web sites, social media, etc. You can often get advice or peer review from professional scientists by asking them. You might pay them for their time…
Not to say it's impossible to do science as a hobby (there's some good stuff coming out of e.g. the ham community and amateur astronomers), but sadly most of my interactions with "hobbyist scientists" have been crackpots (ok, there is some selection bias here, crackpots go to all sorts of lengths to try to contact you).