Why can’t an entity be formed for the sole purpose of buying securities?

[Vitaliy Gnezdilov]

Hi, I am looking to invest in a real estate fund syndication and I have received advice to invest through an LLC for a specific tax purpose.

However upon research, I am finding that an organization cannot be formed with the sole purpose of purchasing specific securities. And my question is why is this not allowed?

Source: https://www.sec.gov/corpfin/amendments-accredited-investor-definition-secg

What am I missing?