I think he mostly sticks with a back 3 because of our lack of great CB’s and over abundance of RB’s who are capable of playing(we see Walker at RCB ).
We didn’t/don’t have 2 CB’s good enough to play as a 2 and defend one-on-one on the counter. Also the fact that it’s hard to leave Trent out and he’s notoriously a bit lax defensively despite his obvious attacking qualities.
So Gareth plays it safe and seeks the extra protection of a 3, while somewhat lessening Trent’s defensive responsibilities as a RWB. As well as putting Walker in there for his recovery pace the other CB’s don’t have.
The big unknown here atm is Stones’ return to form and whether that impacts the thinking. Stones-Maguire still isn’t the quickest but with a Walker and Shaw at FB’s we might have the recovery pace(Walker) and defensive ability(Shaw) to do ok. But then what about Trent? It’s a bit of a mess tbh, not a lot of balance to be found.
who knows, maybe Brendan Rodgers can get Leceister to take a punt?
