Some guys get stuck up on the bad ideas that they need to completely keep coins off of exchanges, yet then they end up screwing themselves if they end up having 100s of transactions with $10 to $50 each, so then to combine all of those transactions in the future, the person ends up having a lot of expenses based on transaction fees, and so it is not ONLY the fee that they exchange charges, yet the size of the UTXO can become unspendable if a bunch of small UTXOs are created. Guys might not realize that it might be better for them to wait until the withdrawal reaches a certain amount (such as $500 or perhaps greater than 500,000 satoshis or some other reasonable ways of assessing whether and when to withdraw from exchanges into private wallets).
My post only says about withdrawal fee but you are right about what will happen after withdrawals from a centralized exchange account. In your non custodial wallet, you will receive and have many small UTXOs that will make your transaction size in future transaction very big and it costs you more in on chain transaction fee in future.
This site is simple to check transaction size with input, output UTXOs and script types.
https://coinb.in/#feesIf people want to have something more details, but harder to use, they can use
https://jlopp.github.io/bitcoin-transaction-size-calculator/https://bitcoinops.org/en/tools/calc-size/You can look at historical rates and current happenings on these two websites, too: