If this is really a factor in the stock price, then that company is toast.
When an employee is hired, the assumption is that that employee's all-in hiring cost is less than the increase in value for all shareholders. That means if you pay an employee $250K a year, including stock, the shareholders better be getting more than $250K back in value.
By your reasoning, the shareholders are losing more by dilution than they gain back by enterprise value. If that's the case they should fire everyone and close their doors, since there's no RSU dilution at all with zero employees.
On the other hand, if employees were hired with the assumption that they were worth the price, then any layoffs should rationally reduce the stock value - because even though you get the RSUs back, the employees must have been worth more than those RSUs or it was a mistake to hire them in the first place.
