No, they're still uploading the same data as they did before (last I looked into it, it was still enough data to rather easily reverse and get pretty good accuracy. if it wasn't accurate, it would have unacceptably many false-positives, so it's a necessary quality of the system).
Regardless of how you hash them, it needs to work on a phone, and it needs to be reasonably unique... so you can just enumerate literally every phone number ever on a decent computer in a few seconds and, if combined with basically any other information at all (like an area code), that's enough to figure out many or most contacts trivially.
The difference, which that article goes into, is that now they're going all-in on you also trusting Intel's SGX and thus every single thing in between you, them, their hardware delivery pipelines, etc. Which makes collecting that data completely ok (it's done securely now thanks to SGX!), because you should obviously trust Intel because CPU vendors have had such a fantastic track record in their on-chip security systems. ( in case that wasn't clear)
There's a lot to like about Signal's privacy, both in isolation and in comparison to other messengers. They're doing great work. But I have absolutely no idea why they persist in this data collection. Their bull-headedness on zero options around it for years on end smells more suspicious than anything else at this point tbh. About 3/4 of the people I've known who installed Signal immediately left forever because someone they knew contacted them to say "welcome" and they got super creeped out wondering how they knew they had joined. And then the contact-er frequently left too because they had no idea it wasn't consensual, and were creeped out as well.