Prices don’t fall if no one produces anything. Not trying to be crass, but this is a little like asking what the counter argument to gravity is. It’s just reality, having sound money doesn’t mean there will be utopia, it just means the intervention is wrong and harmful. Sound money doesn’t result in perfection, it simply fixes one extraordinary and systemic problem we are causing for ourselves. But to simply answer the questions, no, there is no new incentive toward malinvestment or sitting around and doing nothing.

You could make the reverse argument: suppose I exert a certain amount of labor (work a job, perform a service, sell a product, whatever). If I do it today, I get paid 100 sats. If I do the same work at some point in the future, and if we assume deflation is a fact of life, I get paid only 90 sats for the same labor. Conclusion: better to work hard today than wait until tomorrow.