Maybe, maybe not. I think it's a far easier sell/better overall campaign for Trump to go after the very core of the Left in terms of bringing it up to national attention and forcing the Left to have to defend it before the public at large. Destroy or even severely damage that, and the rest is dominoes.
Down vote me all you want, but the wall was a waste of time and symbolically stupid. That was always going to be a hard sell since it would be unprecedented so far as the public at large is concerned. I mean really, how do you sell that to people who aren't hardcore conservatives? As you said, it would have been better to go after immigration law (or sanctuary cities for that matter).