That’s true. You could implement a pwm start offset also like this:
It’s just the start offset, no manual modulation.
Renoise 3 simple PWM using reverse saw with start offset
But you will hear now some pitching on higher values.
What’s really missing in the sampler modulation is a play/loop position offset.
If you also believe that the sampler modulation should be able to target the sample position/loop position,