That is not true at all. Just because previous milestones have not had a significant impact on share price doesn't mean they are non-material now. In fact most milestone releases bumped up the share price for at least a few days but eventually settled back down.
Look around at a lot of other companies on the venture these days. There are a lot of cases where material information is released and it does diddly for the stock price. Thats the state of the markets right now and not a reflection on the impact it has for a company. Company milestones are milestones for a reason, as they are considered a significant development forward for the company and they will be announced when ready or required.