They can be good resources, but depending on the condition they can also be a huge source of misinformation. Don’t take any one group too literally because some of them become echo chambers of misinformation and actively hostile to anyone who disagrees.
There are even a few chronic conditions that attract a lot of incorrect self-diagnosed people who insist they have the condition despite every test suggesting they don’t. For example, many people self-diagnose as having various thyroid disorders based on vague symptoms (or WebMD, etc) but won’t let go of the diagnosis when all of their thyroid tests come back perfectly normal. This leads to weird social media bubbles where people insist the tests are wrong and start sourcing their own medications, with predictably bad results.
Low testosterone is the current big trap for men. You can find social media groups that claim that testosterone is basically a cure-all and that the current reference ranges are far too low. Again, they’re usually quite confused when they finally get a testosterone prescription and it doesn’t fix all of their problems like the Facebook groups or TikToks led them to believe.
Be careful out there.