This is worth a read.
https://wise.com/help/articles/2971625/i-want-to-cancel-a-transfer-i-havent-paid-for
TL;DR a Wise transfer isn’t reversible, once it’s marked as ‘complete’. Before then things could go wrong.
Yes it’s no differnt to a bank transfer, really, i.e. no protection really.
Currency exchange rates are generally very competetive though, I use it as an intermediary to transfer £ from my british account to my € spanish account, and vice-versa., so zero risk if I’m happy with the exchange rate.
I’d only use it to transfer currency to trusted friends etc. outside of my own accounts.
EDIT, what’s the value of the bike? if it’s only a couple of hundred quid he might as well just do a direct bank transfer, or withdraw the cash from an ATM even if the rate isn’t great, it’s only going to be a couple of quid difference between a good exchange rate and a bad exchange rate on a ‘small amount’.