I had never made muscles a requirement in a guy, but then I started dating this classic rural farm boy, who worked out a great deal. Nuzzling his beautiful naked, rock-hard chest was heavenly, my first & only physical hunk experience.
The first time I went to a gay club with him, where most of the guys took off their shirts on the dance floor, I actually got light-headed when we slow danced. He was a little taller than me, and I just closed my eyes and rested my head against his bare chest, my mind spinning & dizzy from the rush.
We were together about 2 years (he wouldn't remain monogamous, kept playing around), but since that time I've not made muscles a priority, certainly not an obsession or fetish with me. Yet I can definitely see their attraction, and I wouldn't turn them down, that's for sure.
Lots of us have narrow preferences in a guy, and I can think of worse ones than muscles. I wouldn't worry too much about it, as long as you don't let it blind you to other aspects about a man, both good & bad.