“Mint My Desk notes however that any concerns raised by these employees should be done in a respectful and courteous manner."

But also:

"While employees said they had raised concerns since early 2022, Yu said she became aware of issues on Saturday."

Sounds like a year and a half of "respectful and courteous" failed to get the action that a few days of walkout did.

If you want your employees to be "respectful and courteous" you need to treat them with respect and courtesy. Full stop.