Well as always, depending on your use case and your threat model, using those swap services might not be the best idea, specially if you want to be "stealthy" when purchasing or selling xmr.

If you buy or sell XMR in simpleswap and use a KYC'd coin (like BTC that you withdrew or deposited from/to a CEX like kraken or binance), then authorities can ask the simpleswap owners and they will show them that you traded Monero.

Again if this is not a concern to you, then perhaps those swapping services are "good enough", even though I have read countless stories of them performing shotgun scams and shotgun KYC where they will randomly select you and make it very difficult for you to recover your funds, especially if those funds do not come from "trusted" sources aka another CEX.

But again as always, that is up to you and your use case / threat model, and the risks you are willing to take.