Populist Republicans: Why are you not Democrats?

So, I am actually genuinely curious at this point because to me, I feel like the party has basically no place for it in a serious capacity.

1. On economics, populist reps tend to lean toward M4A and government intervention. The GOP however is basically cutting property taxes and leaning toward 1920s corporate entrenchment.

2. On foreign policy, they are pretty much opposed to populist isolationism

3. This leaves issues like immigration, culture etc - but is this really enough to warrant being a Republican? Like if by the time you guys are 40 and Medicaid has been shrunk to basically a dual enrollment program and the spending cuts from the current admin bare out - what will you be doing, supporting a party all the way till then just so you can get power and somehow create it in your own mold?

Like it seems to me the GOP basically has no point but to defend the upper and upper middle classes - which is where its leadership came from anyway predominately. Each time the only thing they really get done is a tax cut and basically that’s it. Populist republicans then get sent to pound town by getting the exact opposite polices.