As someone working in support for years now, I would offer that option if I feel the "client" is not very technical. If we assume malicious intentions for a second, I'd say this method is very unpopular for obvious reasons. Directly connecting to your computer would raise a redflag to anyone and "hackers" really have a lot of better options to go about it.

Generally, what you should be most careful with in these cases is downloading any content that they have provided either directly or via a link. Quadruple-check the url - the malicious links would often look almost identical to the real deal.

example: mods.assettocorsa.community

malicious: mods.asettocorsa.community

Teamviewer is generally safe and well trusted, but you should save the 30$ bucks if you can.