Vitalik Buterin wants big money to hold off on investing in Ethereum.

...but institutional investment will no doubt boost the price and overall size of the Ethereum network - so what gives?

Think of it like this:

Vitalik is building a theme park in cyberspace (aka Ethereum), but not everything is ready just yet...

A few rides are still in development and large swaths of the park are still taped off, which means it's only really capable of operating at a lowered capacity for now.

If he were to push to open the place up to the broader public (institutional investors), in the hopes of an early pay-day, this may well lead to unwanted attention from safety regulators (the Securities and Exchange Commission).

...who will most likely punish Ethereum with heavy handed regulation, for opening their 'theme park in cyberspace' to the broader public, before it was ready.

And given that the closest we've come to building 'a theme park in cyberspace,' was the one we created on RollerCoaster Tycoon, when we were 12:

We'll trust Vitalik's judgement.