What I am looking forward to is if there are any exchanges that enable us to trade BTC/USD without the need to link a USD Bank account. I want to be able to keep my USD funds on the exchange itself (I am aware that it's not recommended to keep funds on exchange) and trade as normal. I would be just withdrawing the funds in crypto as the time comes.
Have you ever heard about STABLE COINS? For example, the famous stable coin tether? It is a simple replacement of USD. Tether is a crypto and its value will be always 1 USD. I believe now you may understand why you never need a bank account for trading bitcoins against fiat (for example, against USD here as per your requirements).
Still, you may need to clear KYC in come good exchanges to enjoy full freedom with them. I recommend bittrex for trading BTC against tether and you need to submit your ID proof and no bank account required. There are many exchanges are available to trade BTC this way even without submiting your ID proof. But, enegaing with good and reputed exchanges will eliminate lots of hassles.
I don't want to trade between the cryptocurrencies because almost the entire crypto market follows the trend that Bitcoin takes on (more or less).
Now I confirm that you never come across about stablecoins. It is almost 5 years that tether has taken the places of needing USD nor bank accounts for trading bitcoins against fiat. Tether is still a crypto but it acts like a fiat, its value is fixed always.
You are right, I didn't know much about the stable coins, I just read about them once but didn't think of using/trading.
Stable coins fit my needs as their price would remain constant irrespective of the price of Bitcoin(my previous assumption for wrong).
I believe that most exchanges would allow me to trade, with some maximum threshold, without the need to fill out the KYC.