The thing described is far from separation of church. It is straight out oppression.

What other options are there though when the other side has zero interest in secularism and will do whatever they can to institute a theocratic government when given the opportunity?

Some (most?) forms of Islam are just not compatible with western style democracy and secularism. It’s unfortunate but I don’t really see any other realistic options of solving this besides “oppression”.

Some countries like Jordan kind of partially pulled it off but they had very specific conditions which can’t really be replicated elsewhere.

Some Islamic countries are family businesses that have international recognition as states for historical and geopolitical reasons. I don't take the actions of those countries seriously

How is this (what's described in the article) good in any way?