This is true, but I'd qualify it. I'm MUCH more active than when I started, just naturally, and my heart health / true age stats (for what they're worth) are twenty years lower than when I started. I lost a lot of muscle, but as a percentage, my body fat is nearly half what it was when I started. 10/10 would do again.

Recomping is a huge struggle, you just can't eat enough to add muscle bulk. Cycling on and off is tough because if you don't taper off it, your body is like "thanks for ending that long term caloric deficit, have you heard of cake?". So you definitely need to approach the muscle mass question seriously, but in no world was I healthier back when I had an extra 10 to 20lbs of muscle, and the rest in fat.