It definitely doesn't hold 150 yards of 50lb.
It's supposed to hold 150 meters of PE 2.0, which is normally about .235mm or so, which equates to about .010 inches. Might be closer to .009 actually. Too lazy to break out the calipers haha.
So that would be roughly 164 yards of .010 line give or take.
I think that was a misprint or a miscommunication somewhere on the 50lb part.
I use either 20lb cortland braid which is .010 In. Or 30 lb which is .012 in. (Can't remember which I have on there.)
There is easily more than 100 yards on there, which is more than enough for myself. I personally think the line capacity measurements are a bunch of crap anyway, from any manufacturer. I don't think I've ever got a stated line amount on any reel I've owned. It's always been in the ballpark, but not exact. YMMV
I use mine for deep cranking, 8xd, 10xd, azuma Zboss, cloud c25, etc.