No, only the M3 Pro processors have fewer P cores (5P+6E/6P+6E on M3 Pro vs 6P+4E/8P+4E on the M2 Pro)
The entry level M3 has the same number of P cores and bandwidth as the M2 (both are 4P+4E (100GBps))
M3 Max has more P cores than the M2 Max and only the lower P core M3 Max model has less bandwidth (10P+4E (300GBps)/12P+4E (400GBps) vs 8P+4E (400GBps)).
We'll need to bench for waitmarks to be certain, Apple showed some good performance improvements for the new cores. And the GPU has ray tracing acceleration now
Well, there were M2s in the comparisons too, I'd say the improvement is still good, but again we should bench for waitmarks before jumping to conclusions here
Not really. the M3 line has less bandwidth and fewer P cores compared to M2.