Solo 401k for real estate investing

[Sam Dal]

Folks

I have been doing some reading on this topic. I am a passive investor and typically invest directly in apartment syndicates or funds. Given returns are fairly muted now and historically the stock market has returned approximately 7% annually, does it make sense moving from a regular 401k to a my solo 401k and investing that money in real estate even though there are no tax benefits to be had. I see some folks doing it but don't understand why since a 401k is completely tax-free growth in the first place

thanks

Thx