This appears to be an ever-changing situation, but it seems from this article that most other carriers are taking a harder-line with mask usage than Southwest -- at least as a requirement to board.
Airlines have instructed flight crews to not let masks lead to in-flight disruptions
In a memo sent to American Airlines pilots Monday, the day the mask policy went into effect, the carrier said enforcement of the requirement around face coverings would depend on where a customer is. At the gate, for example, travelers can be prevented from boarding if they are not wearing a mask.
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United Airlines says its mandatory face-covering policy is enforced first at the gate when passengers board, then “flight attendants inform and remind customers of the policy during flight in ways that are similar to our other safety policies.
Passengers who refuse to wear a mask at the gate will be pulled aside by a customer service agent to discuss options, including moving to a new seat where they can stay a safe distance from other passengers. An airline statement said an “isolated situation where a customer may be denied boarding as a last resort” could be possible.
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In a statement to The Washington Post, JetBlue said that under the new policy, its crew members will be “sensitive to all situations, using their best judgement to maintain compliance while upholding our service standards and will try to de-escalate issues onboard to the best of their ability.” The statement also noted that customers who choose not to follow the mask policy will be reviewed for future travel on the airline.
