Are Normal games generally harder than Ranked?

Abolutely not.

Depending on the average MMR of the games and who is playing in them. (E.G. if you are facing 5 diamonds in a normal game then it's going to be a lot harder than if you are facing 5 bronze players in ranked), normals should tend towards the easier side.

The reasons for this are twofold.

1. People don't take normal games as seriously. You are going to find more people farming kills, not caring about wards, and not caring about objectives in normals.

2. People will first time champions in normals fairly often, try new strategies, or simply just dick around.

That being said, people can still warm up their main in a normal game and totally smash the opponents.

nah...people don't take normals seriously

gameplay-wise could technically be harder if you q with higher ranked friends (but win rate should be pretty even)

but let's say you don't take normals seriously either and trying out champions then probably yes in that perspective