Bro, to be perfectly frank, there is no real downside to engineering firms in general neglecting the "people at the bottom", as you put it. That's precisely why engineering is such a poor paymaster in general, cos if you don't like it, you leave and they can find a new and potentially cheaper replacement for you.

Yes, there is some frictional cost as the new hire gets up to speed, but the impact to the business is really negligible.

Why?
1) Because most of the engineering roles in Singapore are those of a manufacturing variety ie process engineer (which is a glorified maintenance technician) or modification engineering (sometimes glamourously referred to as design engineering). There's really nothing proprietary about the knowledge, so nothing lost when you leave.

2) Overseas engineers are potentially better, definitely cheaper, and harder working. Engineers from China and India are extremely well grounded in fundamentals, and those that come to Singapore are incredibly driven.

3) Most engineering jobs skills are not transferrable, so they know its hard for you to get up and leave for a better paying job.

Hence, think an attitude adjustment is in order here. If you want to get paid well as an engineer, you really need to look outside of the box and not do stuff that everyone else is doing.

Thinking normal thoughts like "let the company neglect me at their peril" or "i work hard and the company will reward me" will, unfortunately, never get you there.