You are right and I agree that with so many choices rest has the potential to stabilize players. Especially Arteta did not want to take any further risks. I'm sure what Arsenal gets knocked out in the FA Cup will be very beneficial in the Premier League and only focus on maintaining the Standings. It's no wonder that clubs like Manchester United and Manchester City will be preoccupied with busy schedules and players with a higher potential for injury. If that does happen at least a plus point for Arsenal to be in full control.
That's why a club must have good squad depth, so they won't find it difficult to rotate players and have a large selection of players. With a busy schedule, of course, this is a problem for clubs who are not ready for the depth of their squad, but for clubs who have good squad depth, they will like this situation, because they are very aware that their opponents must be tired with such a tight match. They would definitely take advantage of their opponent's weakness. If the situation is over and they have no other choice, then giving trust to the existing players is the best choice. Trust, yes that is the key, because sometimes a club doesn't really believe in the players they have.
Currently they have anticipated a shortage of players. For Gabriel, who was a bit doubtful when he had to suffer an injury, now he has been fully entrusted to Nketiah and yesterday for Partey, who was injured, now Jorginho has been brought in from Chelsea to fill that position. I think now Arsenal are still very ready and Arteta is really thinking about all the possibilities that will happen and of course that is very good.
This week they have a pretty easy game against Everton and I think it will be a win for them with the current squad.