Our realtor's expertise was useful when we were making an offer, and when dealing with financing and paperwork, but I don't think she provided $50k of value. If I were paying a fairly generous hourly rate for her time, she would have made less than $5k.
Sure, sometimes a buyer's agent spends 100 hours helping their clients, finding and showing property after property after property, and has to deal with tricky negotiations, and is maybe worth the 2.5% commission.
But I don't want to pay $50k for 10-15 hours of work; that's ridiculous. (And of course I was paying for the seller's agent's commission as well.)
Another house I was involved in buying was similar: second house we looked at, only one counter-offer needed.
If/when I buy again I will likely not use an agent. The new rules around not foisting the commissions onto the buyer will help too.