What a bizarre topic. 95% of the historic contributions here have absolutely nothing to do with making dim sum at home (there are more posts about Chinese banking systems).
I understand the lack of home cooking of dim sum posts, though. Few people ever do it. In fact S: 点心; T: 點心, (Mandarin - diǎn xin; Cantonese - dim sum), however delicious, is merely an aside at a social event, 飲茶 (Mand: yǐn chá; Cant: yum cha), drinking tea or 早茶 (Mand: zǎo chá; Cant: jou cha), morning tea.
These places can be cacophonous early in the morning. Conviviality and conversation is the point. Food, not so much.
The food served, the dim sum, often doesn’t lend itself to home cooking and for many items, considerable skill and experience is needed. The best dim sum chefs are highly regarded in the same way as the best sushi or ramen chefs are in Japan.
Despite that, there are many recipes on the internet. Some read OK; most don’t; and some are just sadly clueless.
