I do believe there are managers who could do better
I also don't think it's fair to compare Benitez's only 13 games with Ancelotti's worst 13. Why not use Ancelotti's first 13 rather than his last?
Well, it was Everton's last 13 games last season vs first 13 games this season.
The point is, even Carlo Ancelotti had a torrid run which has ran into this season.
Changing Benitez now or anytime soon, doesn't give us anything of significance this season. The club have wrote this season off.
I wouldn't give Benitez, or Brands a penny to spend in January. We made that mistake with an interim boss in Allardyce and a DoF on borrowed time in Walsh when we paid a lot for Tosun and Walcott when we weren't achieving anything that season, or going down.
Ultimately...
A full fit Everton team and we're 6th-10th.
A few injuries and we're 10th-16th.
The margins between those league places are pretty small. We're as close to 5th as relegation right now.
It is what it is.