Is getting a second masters in a different technical field worthwhile? If a person has a degree in one technical field and sees and opportunity to obtain another from an even higher ranked university in a field that has great synergy with where they are now, is it worth the time and especially money spent? By worth, I mean would having a second masters be a significant benefit for someone working in industry?

That is the general question. In my case I will have an M.E. in Systems Engineering and about 4 years experience programming in an engineering field. I am looking at a Data Science program at a top university, it would be a year and a half and lead to an M.S. The cost of both is considerable, I am unsure that the benefits outweigh the costs.
A Masters degree is fundamentally different than Ph.D.  Whereas a Ph.D. teaches the general skill of scientific investigation (in some context), as Masters degree focuses on acquisition of a particular set of skills and knowledge.  If it is just the skills and knowledge that you want, it is often possible to acquire them elsewhere as well.  

The value of enrolling formally for a second Masters degree thus comes from one of several corollary benefits of formal rather than informal study:


You want to make a career shift to an area where a Masters in a particular field is a pre-requisite or of high salary value.
The formal program will allow you to focus more strongly on skill acquisition, either because of the expectations set by classes or because formal enrollment will provide financial benefits (e.g., some employers have degree program benefits).
The program will give you access to resources (e.g., high-end lab equipment, mentoring by professors) that are useful for acquiring the skills and difficult to get access to otherwise.


Whether the cost/benefit tradeoff is worth it in your particular case is something that only you can judge, but these are good metrics to use for analyzing that tradeoff.