Actually, yes, it does. You agreed (as did everyone that can play the game and post here) in said terms of service that anything could change at any time without notice. It's not being a lawyer, it's reading a Terms of Service agreement and doing more than simply clicking OK. It is about knowing what will and won't be allowed (on both sides). This was an explicit and implicit term: They have full right to change anything they see fit.
In theory they can change anything at any time, but in practice any change that can be construed as misleading or deceiving customers (i.e knowingly leading customers to expect something different from what is delivered) constitutes a breach of contract.
Anyway, that said, something does need to be done about there now being an incentive to dispense with all other Science consoles in favor of multiple Field Generators. Perhaps it is not the Field Generators that are too strong, but the skill-buffing Science consoles that are now too weak to compete? The fact that many players were using Science console slots as "dump slots" for Universal consoles already speaks for many Science consoles being perceived as less useful.