I live a whole-food, plant-based lifestyle and have for several years now. No meat, no dairy. Whole foods that are plant based. No need to count calories and I've never felt better - I feel better in my 50s than I did in my 20s and 30s.
And before you ask "How do you get enough protein?" Let me ask you, how much fiber do you get? 97% of Americans don't meet the MINIMAL requirement for fiber intake
Two great reads are Proteinaholic by Dr. Garth Davis and How NOT to Die by Dr. Michael Greger. It's not a diet, it's a way of life now.