The "leader" has no choice after they win the current round but they do have a choice as to what to include in the winning block before they start hashing.

Maybe they act like all the other rational miners and optimize by mining fees.

Maybe they include no transactions and only take the miner reward.

Maybe they they don't like the Dutch so all their transactions are excluded.

It really doesn't matter as all y'all have been arguing over is what to call the person who won the current round.

Everybody has that choice before they win the election, so are they all leaders?

You really don’t see how this terminology is completely incoherent for this scenario?

They become a "leader" when they get elected, so only one of them becomes the "leader". There's nothing incoherent about this terminology.