People eat Horseshoe Crabs? No way, but their precious blood give me
'eaten as a delicacy in some parts of Asia' according to Wikipedia, but to be fair OP is only asserting possibilities anyway (the criteria are 1) old enough to have been around for dinosaurs to eat; 2) edible by humans).
Technically they eat the roe. Horseshoe crabs have very little meat and it’s so tough as to be practically inedible.
'eaten as a delicacy in some parts of Asia' according to Wikipedia, but to be fair OP is only asserting possibilities anyway (the criteria are 1) old enough to have been around for dinosaurs to eat; 2) edible by humans).