I don't advice anybody to use those anonymous services started by brand new accounts. Before all, telegram is the worst place to start with, for both lunchers and users, especially with those confirmed bot use.
The service has no known reputation so it's not trustworthy until proving the opposite.
Totally understand your concern, but it's totally misplaced in this case. I'm community manager of NEXT.exchange and we have about 6000 people in our chatroom. What Hulibot does is exactly the opposite of what you are giving a warning for, the bot blocks all the viruses going around these days. It blocks spam, unwanted links, you name it. And the best of all, it has a 'bot check' upon entry. This means that we are 100% certain every user that enters is not a bot! It gives a safe environment for all our users without spam or anything.
So yes for me this bot has fully proven "the opposite", and is the only bot I'll trust in telegram. It has all the functions you'd want managing a community.
Peace!