It was applied "after the play was over" because the linesman was running down the sideline to spot the ball for the next play when he ran into Pete, thus delaying the spot late in the game when clock was important.
It was a "good" foul, well within the rules and Pete said so at his presser. Just be thankful we can laugh it off. Like was said above, we got the 1st down and didn't lose it on the foul.
I kind of get that, but a delayed spot realistically doesn't harm either team in that situation, and certainly not the offense, to whom the quick spot generally matters, since NY can't force us to snap the ball or even return to the LOS.
If NY had been driving down the field and the spot was delayed by Carroll sure, it's a clear penalty. But when your team is on offense how does delaying your own spot ever provide any advantage to you. Arguably if the ball goes OOB you could suggest you get an extra 5 seconds to think about the play, but the clock stops, so no real advantage there in winding down the clock further, though you could argue it gives you an extra few seconds to think about the playcall before the playclock restarts when the ball is spotted.
In this case Geno was in bounds so the playclock keeps running anyway - you aren't forced to snap the ball in any case, and since Geno slid in-bounds and the 40 second timer started immediately, the clock doesn't wind down any faster or further as a result. The ref taking an extra 5 seconds to spot the ball doesn't change anything there? If anything, if we were chasing the game and Carroll stopped the ref it would work against us since clock keeps ticking down and slows us down from snapping the ball, so to get a penalty for doing something that actually disadvantaged you would also be a bit counterintuitive.
I agree the penalty didn't impact us in the end so redundant, but just couldn't see why they didn't pick up the flag and restart the playclock other than they stopped it to talk about the penalty which never needed to be thrown!