No. Rooney was a better talent and we'd be lucky if Rashford has a career that even somehow resembles his and Rooney never had a shot at Ballon d'Or. Also, Rashford is brilliant, and he's definitely one of the brightest young talents in the world, but Mbappé's natural ability is on another level, unless he gets a serious injury, no one from the current crop is catching him.
Rooney is a weird comparison as he was also the better looking player out of him and Ronaldo for quite a few years. He just never really pushed on...if it wasn't for that and the fact Ronaldo and Messi exist he probably would have been competing for Ballon d'Ors. I also find "can reach Mbappe levels" a weird statement though as Mbappe is younger than Rashford so this doesn't really make much sense. Mbappe arguably has more scope for improvement than Rashford does.
I've thought for a long while now that Rashford has it in him to be among the best in the world. He's got the ability and the selfish streak to get there, and his work rate gives him an edge over a lot of other players who might otherwise be at a similar level.
I'd say natural ability wise Martial was probably ahead of him to start with for example, but Rashford is easily the better player now...and that's not really a criticism of Martial. Some players just have that bit of extra drive for some reason. It's what players like Ronaldo and Bale had at Rashford's age and that's one of the reasons they reached the level they did.
By last season, presumably you meant from Dec until February (after PSG/Liverpool game) - so around 3 months?
Rashford has performed well for his age, but we need him at least start delivering over an entire season, becoming more consistent and improve his lower levels
He scored 27 goals for us in very little over a year for us leading up to his injury, mostly as a wide player. I mean that's impressive for someone who's inconsistent. It's better numbers than you'll find from the likes of Salah and Rashford is playing for a team that has largely struggled in that period.
He did have a really poor run at the start of this season but I'm convinced he wasn't fully fit during that time...the fact he was either limping around or having to be subbed off towards the end of every game at the time was kind of a giveaway to be fair.
Honestly I think at this point Rashford's biggest obstacle is he's in danger of being held back by playing for a struggling team, although hopefully it works the other way and he's one of the players who helps push the team up a level.
I think you'll always get inconsistency because he is such a direct player. He doesn't play safe balls often so he'll have games or spells where things don't come off. Ronaldo was always the same to be fair, and I'd be happy if Rashford got anywhere even approaching as good.