delegation of stake to 25-100 block creators by unlimited number of users

vs

delegation of hash power to 3-4 mining pools by unlimited number of users

it's very similar in how validators are chosen through decentralization

but you can argue less time tested with less understood attack surface

users also have the ability to fire bad validators on dpos costing them income or change total numbers via committee/DAO like on pow they have to point hash power to different pool