You've lost the plot mate.
In case you hadn't noticed, and you happily state that you don't bother watching the games (which explains a lot), Reguilon played yesterday. He didn't do anything amazing, but certainly didn't do any worse than we've seen from Udogie this season.
Do you really not think that had he been used to rotate earlier in the season then we might currently have 2 fit leftbacks, and maybe even some semblance of form between them?
You can laugh all you like, he is a fullback, and he is in the squad, literally selected by Ange himself.
He's been sat kicking his heels most of the season whilst our first choice was flogged to breaking point, whilst we played a cm and emergency right back out of position, whilst we played the back up right back who can't get any rotation minutes at right back there, and I'm pretty sure we also played "not a left back" Ben Davies there at some point too...
Tell me, how's that worked out?
Only to now be in the position where Ange has to turn to him with his tail between his legs anyway...
Sorry Reg, I've broken everyone else mate, now go out there and play your heart out for me would you?
Inspirational.