The issue is above all that bridging to Telegram (a proprietary, centralized service) basically amounts to normalizing and encouraging proprietary services. The poor UX of bridges is a secondary issue.
You’re not the first person to seemingly have missed that I offered to bridge the XMPP room to the Matrix rroom, provided Telegram was de-bridged…I suppose it’s not clear from my writing.
The post already explains in painstaking detail why network effect requires us to adopt extreme measures (which you mischaracterize as “you’re either with us or against us”). It’s the nature of the conflict, and free software advocates must either recognize it, or continue to suffer the dominance of proprietary software.
The issues with Matrix are perhaps better explained by others, elsewhere.