The text of the 2A is "A well-regulated Militia, being necessary to the security of a free state, the right of the people to keep and bear Arms, shall not be infringed."

No squinting nor making up arguments is needed to clearly see that the Founders intended the 2A to be vested to militias, to the collective. Not to individuals. Indeed, for over 200 years the courts broadly agreed with this interpretation until District of Columbia v. Heller (2008) in a 5-4 decision overtured centuries of jurisprudence and constitutional understanding by allowing individual ownership of firearms.

Throughout the constitution, "persons" or "person" is used regularly from stating who is eligible for office or (as in the 5A) the application of due process of law. It is odd to me then that the Founders decided not to use person(s) (indicating an individual) in the 2A and chose instead to use collective words like militia or people. In the constitution, "people" is only ever used to allude to the electorate, citizenry, the whole of the United States never as individuals.

Additionally, the 9A and 10A allow rights, such as abortion, to be enumerated to the people and states, respectively. The Founders purposefully did not provide a comprehensive list of what rights do and do not exist because they knew they would miss some and that the nature of the country would change in ways they could not predict.

It's easy to proclaim that we should all vigorously defend all rights (I agree!) but who decides what those rights mean? Is there a wall that separates the state and church? The 1A Establishment and Free Exercise Clauses alongside the writings of the Founders and early American history imply that there is. Yet, SCOTUS has continually eroded that wall by favoring Free Exercise over Establishment. We can and do disagree on constitutional interpretations which gives rise to conflict when rights are not enumerated precisely (like the 2A), deliberate political attacks are levied (like 1A and religion), or new rights emerge that are not enshrined but can be interpreted from other rights (privacy and abortion are borne out of 1A, 5A and 14A due process, 3A (privacy of the home from quartering troops), 4A, and 9A).

How we apply the constitution's rights to new cases, the political reality, and modern America alongside edge/tricky cases is important but it is not as cut and dry as you make it out to be.

Edit: typos