Is it OK to use Telegram or Twitter DM as contacts instead of email or Intercom chatbox?

Do you mean in-app or on a page?

I'd rather contact a service through Intercom/Drift/... or basically something that gets my message to a human than switching to another app or site, in this case it's about convenience in my opinion.

If I really look for help and there's nothing on the site or in the app I look for support elsewhere but not as my first option. :)

If your audience is fellow indie makers then maybe. Still having a dedicated place for handling your business is better than having it mixed with random things on Twitter/Telegram.

Thanks. This makes sense. Twitter/Telegram are convenient for me as I spend most of time there but not necessarily for customers.

In all seriousness I would definitely have email for normies

Make it as easy as possible for people to contact you.

Drift, Intercom, etc. on page are way better than requiring someone go out of their way and open another service.

Consider it a sales tool.

that makes so much sense as it doesnt require login or a third party app.

Rather have a contact box and ask for their email address with a message within your site.
Let any submissions go to a DB or Email yourself.

@marcantoinefon (Corgi) is building something that notifies you via telegram.

And then you can just respond via email manually if its worth your time.

Also, no more spam... I got a lot of spam when I had my email addy on my site.. It disappeared after I replaced it with a contact box. :D