Do not be too happy that big and giant companies are entering the field…
Because they set the price up and down whenever they want…
You should be happy when ordinary people invest more than big companies.
In simpler terms, it is much better if bitcoin or anything else that exists is distributed all over the world and reaches individuals and companies equally, or, as the saying goes, does not accumulate together.
Wherever governments or large corporations stand, they are sure to determine everything.
Successful and healthy

You or anyone can't do anything about that. You can't stop those "giant" companies from entering the market or put any restriction. After all, its a free market. But it is not like "one" single giant company is hoarding all those bitcoins. Hundreds of companies together are doing it. And I am pretty much sure, if we combine the coins of all regular users, we will see that those giant companies actually hold a negligible amount of coins. And, the supply isn't over yet. If those companies wants to own majority of the coins, they will also have to buy all newly minted coins. Would be interesting to see that happen.