How did tvb writers recruit?

Sorry, I'm not a professional. I used to hear that TVB writers are insiders, that is, relatives of old writers and so on. Anyway, they have to have connections to get in. If they don't recruit outside, the script will definitely not be publicly solicited. Sometimes a play can have dozens of screenwriters, just like "A Good Home and a Full Moon", which is a collection of three generations of screenwriters, and the list is particularly long.