Equal protection under the law isn't Marxism. However, calling for the breaking of the nuclear family for making "extended" families of making communities responsible for raising children is one Marxist idea. It literally is. Welfare as a whole as well as social programs are Marxist by nature. Forcing someone, either directly or indirectly, to provide for another to make them "equal" is the corner stone of Marxism.
Abolishing prisons, police, and calling for a "sustainable" redistribution of wealth is also all Marxism. The ideas of equity and not equality of opportunity is Marxism as well. Which is left-wing ideology. Marxism is a means to realize left-wing ideology. It is a codified solution to that goal. It uses the bridge of inequity as a leverage to spread its ideas. Inequity doesn't just mean through socio-economic differences, although that is one of the linchpins of the ideas. Perceived, whether real or not, of inequity of any social class can be used which includes racial distinctions.
Yet another example is trying to pass medicare for all. That is socialism. But they make it a "racial justice issue"
The idea of racial justice, aka the defining of the oppressor class that needs to be overcome by the oppressed is Marxism. The removal of a profit in the health care industry, or any industry, is again Marxism.
Thousand Currents, which underwrite BLM, said their goal with BLM was to create "equitable and just societies" which is straight out of the the Marxist playbook. Just by what measure? Just by equity. That isn't a call for equal justice that is a call for equitable and just. It is a difference with a distinction. Of which is the company that pushed in Oakland, as they are based there, for the whole new $500 UBI for all non-whites there through the mayor. Wealth redistribution is again Marxism.