The alternative is liberalism or the absence of planning.
I highly recommend Hayek's Road to Serfdom for more details.
Without rule of law there is barbarism. Any law infringes 'freedom', the thief's freedom, the plunderers freedom, the polluters freedom, the arsonists freedom, the greedy fisherman's freedom, so whose freedom are you going to protect and whose freedom will you take? And if you take someone's freedom they will not consent so you need force.
That means you need planning to develop rules, to convince the majority to agree to the rules, a system to enforce the rules and reach some kind of ongoing consensus for any sustainable peaceful society. And you are back to a society with planning, rules, democracy, governance and loss of 'freedom'. Even a basic marketplace needs 'planning' and rules to function so this 'market as planner' thesis seems aspirational.
But try for a moment to see it from a fascist's perspective. Who they care about, really? It's easy to only see one's peers, and not so hard to feel contempt towards outsiders. I bet that from the inside, fascism can easily feel socialist. A current example I think would be some anti-fascist groups, which despite their stated goals can be pretty fascist.
I guess no one told the soviet union about their antisemitism being incompatible with their ideology.
The British Labour Party is similarly engulfed in an anti-Semitism scandal at the moment, it’s all over the papers.