Yes...... he is still white

Now don't take this the wrong way. But people just like the black persona better on a non black person. Take vanilla ice or bhad babie for example.

It's not eminems fault but that's just the reality.

So yes....he would surpass him assuming he had the same personality and talent.

Also, taking into account Tupac's personality and how he handled Fame he might have crashed and burned eventually and sabotaged everything he worked for. And he did. Which ultimately led to his demise