The 2nd amendment has never needed to be "incorporated", except in the minds of those who wish it didn't already apply to all governments as it is written. Including some dreamers on the Supreme Court. The 2nd already WAS "incorporated" by its own original language - something not true for all amendments.
Different amendments are aimed at different levels of government, according to their plain text. Surprising how many people ignore that fact.
The 1st amendment says "Congress shall make no law...." and then goes on to name a number of things Congress is forbidden to interfere with. It carefully did not say that states were prohibited from affecting those things. That amendment was clearly aimed at the Federal govt only when it was written.
Later the 14th was written, and said that states can't deny their citizens the privileges and immunitites protected by the Constitution. Hence the "incorporation" of some more-narrowly targeted amendments like the 1st.
But when the 2nd was written, it's was not restricted to just the Fed govt like the 1st was. It simply said that since militias were needed, the right to KBA cannot be taken away or restricted. Period. That meant, by ANY government - Fed, state, local etc. The 2nd was clearly "incorporated" already by its plain language, where the 1st clearly was not.
Only after the 14th was written did the one-size-fits-all weenies start pushing the idea that NONE of the amendments were "incorporated" - a clearly false premise for some of them. It was also useful to fabricate a "loophole" by which the anti-gun-rights people could pretend the 2nd only applied to the Fed, despite its clearly inclusive language.
Did the 1st amendment need to be incorporated? Maybe, though that tended to change its original purpose (leaving states free to have official state religions, for example, which many states did when the BOR was ratified - a situation no longer true). And the 14th *is* part of the Constitution now, so incorporation technically happened the instant it was ratified. It's just taking the Courts etc. a while to catch up.
Did the 2nd amendment need to be incorporated? Simply, no. It already was. Unlike its effect on the 1st amendment, the 14th changes nothing WRT the 2nd. Again, it's merely taking the Courts (and the gun-rights-haters) a while to catch up.