After researching this a bit. It's my belief that the standard awd is limited both in hardware and software.
Ingineer made some interesting teardown videos where he found the inverter for the rear motor in a standard awd is rated at 500 amps instead of the 800 amps in the P.
At the same time I don’t think this inverter difference can be solely responsible for the full second difference. Much like people were finding the RWD could put up 0-60 times in the 4.8 range until a later OTA update corrected this back down to the listed 5.1 time. I think the standard awd has a lot more headroom and could go faster, but if tesla allowed that, it would canibalize performance model sales. So even if you see people claiming the standard awd can go faster than tesla claims, don't count on that always being the case.
I don’t think Tesla will ever allow making the standard awd faster than it is (unless something crazy happens in the market like porche decides to sell the mission E for like 50k) as that would canibalize sales of the performance.
So long story short in my opinion:
The standard awd at 4.5 0-60 is still very fast
The standard awd us unlikely to get faster
If you want faster you should go for the P3D now
All that being said, I still stare at my AWD config almost daily and contemplate changing.