Assuming lack of interest does not mean underperforming you should consider that, maybe, they hired you because of the job you, virtually, can perform. They kept you after probation period because of your results and now you obviously stepped back then your managers are - rightfully - concerned. If "...soldiers ready to fight..." is their literal wording then it's definitely weird but I'd not give more weight to something that probably is just some team building BS.
In my opinio the main point is time. You worked there for 1.5 years and in this short time frame:
- You have been inducted, you learned about the company, the product, the team, and their procedures (assuming you were already proficient with their tech stack).
- You performed at the reasonable best of your possibilities, possibly better than average.
- You noticed there aren't raises and promotions for your performance.
- You decided (after a year or so) to do the minimum necessary.
- They noted this pattern and talked about it.
Don't you think you have been too fast to draw your conclusions? Unless your performance was stellar (not merely good) I'd consider one year the minimum for an educated performance review.
While your reasons might be perfectly fine (but you had to investigate these issues when interviewing or, at least, during probation) this isn't the right way to handle the problem. As I often say: communication is the tool to solve problems. Explain your concerns and you can try solve the problem together, ideally you had to do this during your yearly performance review.
You don't know their reasons then you can't make assumptions unilaterally. Maybe, currently, they financially can't afford any reward; maybe you were performing well but not better than the others, maybe they WERE planning to give you a promotion after next review (but after a year or so you stepped back). We're just speculating because we simply don't know.
I think that this attitude is terrible both for the company and for your own because it may quickly become a radicate trait of your professional personality. If you can't find a solution together with your managers then maybe it's time to pursue different challenges elsewhere, maybe in a faster environment where good performance are quickly rewarded (but be careful because suboptimal performance are then quickly punished.)