I completely understand that guns are difficult to understand for non gun owners, they simply don't do any research. Couple that with the amount of research required to be knowledgeable takes weeks or even months for even the most competent of us. But imagine what you sound like to someone who is knowledgeable. It’s like someone challenging a PhD on knowledge. You should know what you’re talking about and if you don’t keep your mouth shut.
If you want actual visual proof that the AR-15 is on the lower end of the spectrum then watch this video, timestamped at multiple different locations:
AR-15: https://www.youtube.com/watch?v=T5QNTnMO5xU&t=9m53s
M14 (bigger than AR-15): https://www.youtube.com/watch?v=T5QNTnMO5xU&t=10m41s
Lever Action (still more power than an AR-15): https://www.youtube.com/watch?v=T5QNTnMO5xU&t=11m25s
12 gauge shotgun (and still, more destructive power than an AR-15. Also comes recommended by President Biden!): https://www.youtube.com/watch?v=T5QNTnMO5xU&t=11m53s
In fact, the AR is so underpowered in today's world it's being replaced by the military (this gun has 2x the power of an AR-15): https://www.sigsauer.com/blog/us-army-selects-sig-sauer-next...