Do you plan to handle servers where you need to do some action (like send a message) to join all channels ?
I was scrolling through the home page and came across afew where the only channels you're allowed to access are the verify-yourself or welcome channels.
Probably not. Discord will aggressively captcha you and every server has a different implementation of verification. It might be possible with a captcha solver and then some LLM to figure out the next steps.