Earlier this week, Arthur Schwartz and some West Village neighbor associations made good on their threat to sue the city over plans to repurpose streets for busways and bikeways during the L train shutdown. There’s only one proper response: Don’t give an inch, and make the shutdown plan as good as it can possibly be.

In an extra dose of cynicism, Schwartz is also suing the MTA over the absence of a plan to make the 14th Street subway station more accessible during the shutdown — a legitimate problem, but not the motivating issue for Schwartz and his West Village neighbors.

They’ve always been animated by the specter of traffic spillover onto their residential streets when the city claims space for buses, bicycling, and walking on 14th Street and 13th Street.

The objective of the lawsuit isn’t to get the city and the MTA to conduct more environmental review. It has nothing to do with transparency. It’s not even about winning in court. It’s about bullying city officials into watering down plans for bus priority and safe bike infrastructure — plans that are absolutely essential to keep the transportation system working while the L is out of commission.

And the risk isn’t legal, it’s political. If the city tries to get Schwartz to drop the lawsuit by negotiating to reduce the busway hours or scrap the 13th Street bike lane, it would be a monumental mistake.

DOT Commissioner Polly Trottenberg shows no signs of backing down, telling the Daily News that the suit is without merit. Mayor de Blasio should say the same.

Schwartz and company have repeatedly demonstrated that they don’t care about the imperative to keep hundreds of thousands of people moving without the L train. They’re not operating in good faith and there’s nothing to be gained by bargaining with them. In fact there’s a lot to lose: Giving in to this sort of intimidation would embolden other New Yorkers of sufficient means to take the city to court over street redesigns.

The best precedent the city could set would be to forge ahead with the most effective possible version of the shutdown plan: Busways in effect all day, every day, and more transit priority on the east side of the 14th Street corridor.

The MTA, for its part, should do more to improve station accessibility. Advocates have called on the agency to add elevators to the L stations at Third Avenue and Sixth Avenue, as well as the 4/5/6 platforms at Union Square. New NYC Transit chief Andy Byford is sounding a lot of the right notes about station accessibility in general, though he hasn’t committed to including more elevators than the MTA’s initial L train plan called for.

Committing to those elevators is the right thing to do, and it would deflate the one legitimate complaint in Schwartz’s preposterous lawsuit.