Same for me. On Southwest, my knees fit exactly (slightly touching) without the person infront of me reclining. Luckily I'm fairly wiry and usually angle my butt to the left of the chair, and knees on the right (or vice versa). Or I can put my feet and shins under the seat infront of me.

But a normal "feet on ground" sitting position doesn't work if someone infront of me reclines their seat.