Kotak says that companies like Zerodha are going to close and is it true that companies like Zerodha make pool account & keep our money in that?

The only reason a business like Zerodha can close down is because of something like this -

https://tradingqna.com/t/how-often-zerodha-crash-and-prevent-you-from-trading-effectively

or this - https://tradingqna.com/t/kite-app-login-bug/