Maybe its OK while fees are low. You'll have to look at your onchain footprint. I'm not sure its the best way to get a more private UTXO as muun isn't a real LN wallet. They use atomic swaps.

Sending into a LN wallet like Zeus or Electrum, then looping some out might be better.

There's also liquid (onchain-liquid-LN-onchain)

Or a simple custodial wallet like coinos.io or blink. Send onchain withdraw LN

Conjoins are another option