Much truth to that. And I’ve also discovered that our needs can change over time as our health changes.
Should you become a lean person yourself, you may discover that you’ll want / need more fat on the meat you eat. It’s not wrong if you do, it’s not wrong if you don’t. It’s just what works well for you in the context of where you are right now. (Don’t know if I said that quite right, hopefully you get what I mean.)
Honestly, as I’ve come to a point where I’m pretty happy with my weight and pretty happy with my health, I pay very little attention to “how much” of anything I consume other than perhaps some mental notes on how I feel from day to day and whether that might related to how I ate over the past day or two. It’s been around 7 years now since I went radical and started keto. I was told I was gonna kill myself. Nope. Dropped 100 pounds and have been enjoying pretty good health. I can’t say I’d even be on this side of the sod had I not make a change. Thankful to still be here. 
Probably leaning way more meat heavy than veg heavy these days, I feel better here. Still not all the way to carnivore most days but come pretty close sometimes by accident.
Something that’s also happened to me over time has been that I’ve become less critical of others’ dietary choices. Just as I was free to change what I eat, they are just as free. I might not always agree with their choices but those choices are not mine to make for them.