Is this guy serious or not? So each of these coins that just forked were around $400 per coin? How much do each of these coins now? so basically if you owned 1 bitcoin, you would have 1600 dollars roughly from the bitcoin fork? Is this true or not? I had thought these new forks were where the coin probably would be say 50 dollars a piece only.
He is serious, but getting support among other exchanges and wallets can be tough or requires a lot of patience.
To know which wallets support any new fork you need to go to the website for the new coin (that's planning to try to fork Bitcoin). Most of these will turn out to be worthless. The market isn't going to tolerate 10 different version of Bitcoin.
Coinmarketcap.com (as another person suggested) is a good resource, they don't always start following a brand new coin from day 1.
And the guy claiming he sold some newly airdropped coins (due to a bitcoin fork) for $400 a piece was probably selling them for that much with a single exchange, meaning the exchange was choosing to buy his coins and now the exchanges owns those coins and the risk or reward that comes from it. Yobit was doing that with Bitcoin Gold. You couldn't sell Bitcoin Gold on an open exchange, but Yobit was choosing to buy them from their customers only.
If you want the assurance that you're mostly covered for future forks but don't want to move your coins around to multiple wallets you should keep your funds in a Trezor or a Ledger, those companies tend to honor these sorts of things provided a real market is created for the new coins.