It'll be interesting if today has any impact on Villa's team selections going forward. I doubt they'd have been so poor today if they hadn't played in Europe in midweek, so maybe today could be considered a wake-up call for their need to rotate players. It's not even like they've had to do a load of travelling, because both games were at home.
A bigger side might be more willing to disregard the league cup, but for a side like Villa I would have thought they should be targeting a trophy. Home to Palace next round is very winnable if they go strong, but less so if they go weak. They don't have the squad depth of a City or a Chelsea.
Howe refused to rotate his squad last season when fighting on multiple counts, and it hurt Newcastle. And that only involved six European matches. Villa will have at least eight, and more likely 10+.