What if the person use a decentralized exchange or a noKYC exchange and still use Opay or Palmpay account number which is his or her phone number? OP post is more about not giving out your phone number to buyer and sellers. Giving out your Opay or Palmpay account number which is your phone number can make you a target because some of these people are scammers. You can know their phishing attempts because you have experience already, but there are some newbies that may not know it.
Another thing is that the OP did not specify which exchange but he post is general.
I definitely understand OP’s point and seriously it’s a norm for many merchants now to ask for phone number and the risk there, OP stated to protect your privacy and I was more like privacy wouldn’t be talked about if the exchange is centralized (although OP didn’t specify the exchange was just me since majority use it here) because even without giving out phone number you’re not totally anonymous but yes it is best to avoid phone numbers giving but it only just reduces the risk not totally make one avoid it.
It’s even alarming how traders even ask for phone numbers before even attending to one’s trade. Though and the use of Fintechs are because of the poor network usually faced with traditional banks and this leaves us with little but almost no choice at all.