Based on his pedigree before he got to the QB Developmental Power House known as Penn State

You also can't teach velocity.....the kid has a cannon arm. The whole west coast offense is predicated on footwork. I saw a really good video of Bill Walsh going through his offense once. The receivers make their cuts coordinated with the QBs drop backs. It's all footwork and timing based and coordinated with the receivers. Allar went poo poo when his footwork went poo. Who knows if he can be remade or not but if there is a guy who can do it it's McCarthy and if Allars footwork is remade, you are left with a laser arm who can fit balls into tight windows
Here is what was said about Josh Allen at Wyoming.......
Coming out of Wyoming, Josh Allen’s footwork was highly erratic and disconnected from his upper body, leading to major draft concerns. Because his feet weren't aligned with his targets, his front hip frequently closed prematurely. This prevented hip rotation, forcing him to over-rely on his arm and causing inconsistent ball placement and low completion percentages.The mechanical and physical issues that defined his footwork in college included:
Disconnected Sequence: Allen’s feet and eyes were famously out of sync, as evaluators noted before the draft.Platform Inconsistency: He often threw off his back foot, "arm-punched" his throws, and failed to plant firmly on his intended line.
Platform Inconsistency: He often threw off his back foot, "arm-punched" his throws, and failed to plant firmly on his intended line.
Stance Base: He tended to have a narrow base, which reduced his throwing power and made his accuracy suffer under pressure
In-Game Adjustments: Without a strong supporting cast at Wyoming, he frequently tried to compensate by over-striding, throwing from awkward platforms, and relying entirely on his elite arm strength rather than fundamental mechanics.
Now the same exact things were said about Allar and look at his receivers while he was there. He didn't have OSU receiver talent like Howard did and it wasn't remotely close.
One last thing I will say is I often go back in time and take a look at the Rivals 100 top high school players. A lot of the guys ranked in the the top 50 never amount to anything but
you'd be surprised how many of the all pro talents the game produces were 5 star kids in high school. Allar I believe was the number 1 QB in his class......so was Justin Fields so it may mean squat but I'll draft a top rated QB in high school that has a rocket arm that was mismanaged in college in the 3rd all frigging day long. He's the inverse Kenny Pickett......Kenny performed in college but is on the small.side, has tiny hands, and never had a rocket arm and we took him in the first. Where did that get us.......go with talent!!!