Does trans diy drugs damage troon's skeleton. Or is this just a strong correlation?
Yes, messing with your hormone levels (especially without doctor supervision) can lead to osteoporosis. See:
here.
Doing another brief check-in on
r/TransDIY:
The
current top post is asking about absorbing estrogen through the scrotum (by applying topical estrogen gel).

Sounds like a good way to get cancer or something to me, but hey, I'm just a mean ol' Kiwi... ¯\_(ツ)_/¯
Btw, check out this other troon
complaining about testicular pain:
The commenters tell him testicular pain is totally normal! And you can also potentially use it as an excuse to get a free orchiectomy.
After the EU police shut down Felicitas and Girl Potion, it sounds like "
AstroVials" is now the top DIY HRT vendor still operating in the EU.
https://diyhrt.market/

(^^ LOL at how even troons acknowledge that there are
"concerns" about Otokonoko's manufacturing process.)
Anyway, here's a
recent thread about AstroVials on r/TransDIY:

Sounds like times are tough for EU troons seeking DIY HRT. It's being treated like actual contraband. Makes me smile.

AstroVials is apparently deceptively labeling their troonshine as "skincare oil" or "rose oil", and they're making it difficult for customs to check what's inside without damaging multiple layers of packaging.
This lil pooner (who freely admits to being under 18, btw) wants to know if testosterone will help her become taller:

She also
asked the same question over on r/ftm, where she got more replies (and also admitted being 16 years old). This proves that any "18+" restrictions on these subreddits are just for show; the mods and commenters don't
actually do any policing.
Here's a thread where someone admits to living with their parents and asks for advice on how to hide their HRT injection needles:

The top comment, upvoted to +58:
These posts were on the
front page of
r/TransDIY at the time I'm writing this. I didn't have to do any digging.