Well it’s not the same in a similar fashion of “1 + 1 = 2” is not literally the same as “3 - 1 = 2”. Maybe they accomplish similar goals but downshifting to brake can be done for as many gears as the transmission contains in a stepwise fashion. But without a transmission in a single speed vehicle with regenerative braking it’s more of a “spectrum” of braking and not directly controllable by the driver.
And for the record I believe “engine braking” is a slightly different mechanism than “downshift braking” but could be wrong here - my manual passenger vehicles don’t have explicit “engine brake” controls but a semi truck might.
Downshift Braking is Engine Braking, it's the same thing. And there is absolutely no reason an EV motor could not emulate the exact same behaviour as a stick shift. It's all electronic, you could just emulate the behaviour of a stick shift vehicle there and give the user a joystick with stick shift labels on top. All the motor has to do is to either apply regenerative breaking at a certain efficiency value. The electronics can ramp regenerative breaking from 0% to 100% in any amount of steps you like.
And for the record I believe “engine braking” is a slightly different mechanism than “downshift braking” but could be wrong here - my manual passenger vehicles don’t have explicit “engine brake” controls but a semi truck might.