These are the first and last sentences of your post I responded to.
You don't see how they were pretty direct and pretty judgmental?
It's obvious the OP became frustrated. He's not the first and won't be the last. I have quite a few LED over my tank and have switched out some as well.
My last tank was running for just shy of 10 years. A 110 tall. Not even sure they make that any more

So I too have experience. Back then it was fluorescent and MH and I really didn't have to think about the lights other than how high above the tank they needed to be. I'm not so confident with LED and to make matters more difficult, light measurements don't help much either.
So the OP isn't alone in his questioning the viability or utility of LED. And to state his lack of ability was the reason for his discouragement was way off especially if you don't know the OPs experience.
We post here to share info, learn from one another and to sometimes vent. We generally don't expect to be attacked, though it's common knowledge it happens from time to time :twitch: