People see these hard forks as a chance to get free coins, so they buy up a bunch.
For example, last year november people were buying up bitcoin like crazy for the bitcoin gold fork.
People saw how bch ended up valuable and they wanted to see something with bitcoin gold.
The thing is, buying over inflated coins so you can get a couple free coins that won't be worth much is foolish.
That's like the person who spends way over their budget when shopping so they can get free shipping.
Always, the best strategy is to buy when people are selling, and sell when people are buying.
So, actually, it is a good time to sell your bch, cause it will price correct and you can buy back in cheaper guaranteed.
Agree with your opinion. Its good if the Forked new coin trade on a good price. But most of the forked coins in past has not traded well like BTC-BCH fork. So If I buy now with higher price, it should be compensated with the trading value of coin.