Why not share the content with us here, as it is free there is no difference between creating threads here or in Telegram, and then you leave the choice to the user either by clicking on the link and joining your group or ignoring it.
It is true that now you will get some followers, but they will soon leave, paste some of these signals here and leave some additional features for the Telegram channel.
Trading calls (signals) is a high-risk investment and you should not trust any data without doing your own research.