I find this info about referal:
This is correct information?
When you lead client or freelancer to Upwork, you get 50$ one time, when he/she spend 1000$ ? This is it ?
one time get 5% ? Client spend 500$, and you not get nothing?
Client spend 10.000 and you get 50$?
That is a very old blog post. Please see more recent comments in this discussion https://community.upwork.com/t5/Freelancers/Referral-link/td-p/3045/page/2
Aleksandar has a valid point here:
It makes sense that Upwork does not want to financially incentivize the creation of new freelancer account, because they're actually trying to reduce the influx of freelancers.
But that same argument can not be made for paying clients.
Theoretically, every paying client, which is something the original poster specifically was talking about, is financially beneficial to Upwork.
There may or may not be be great reasons for not having a referral program referring paying clients to Upwork.
But "having too many already" isn't a legitimate reason when it comes to paying clients.