Some argue they perform apartheid on the Palestinian people but those under a different administration. By this logic, every state can be considered apartheid because citizens of that state have in that state more rights than non-citizens. That’s standard.
most of the world isn’t the sovereign in control of the other countries, nor do Americans just annex towns in Canada every few weeks
Democracy index? which one? the economist? they don’t care much about things like civil rights, as long as the majority of the population can vote, the government can enact + Radicalize legislation, if you actually looked up the methodology of the ranking (remember other nations in the same ranking as Israel still have legislation making being LGBT+ illegal and other such things)
18.7% of the population? that’s less than the Armenians in Turkey.
and lastly, on the apartheid regime; if multiple Israeli human rights NGOs, the UN-HRC, Amnesty int., HRW, and even the Israeli supreme court have said it is an apartheid regime then maybe it is.