A 63mm trail is not suboptimal. It's done to avoid handling that would be too quick with a short wheelbase. My Cinelli superstar has a 71 degree sta and 45mm fork offset for a 67mm trail and it handles great. I've done 56 mph on it. It handles great on mountain descents. I was impressed with the handling, right from the start.
Also, some brands never use a small 58mm trail on any of their frames, except maybe the largest.
Last edited by DaveSSS; 09-21-21 at 11:26 AM.