

Everything you’re describing is further speculation and unfalsifiable statements for events which already have a simpler explanation. That’s a tell-tale sign of a conspiracy theory.
Google buying the company as some kind of plot to get spies into Google requires more assumptions than Google buying the company for the technology (as it has done with plethora of other companies). If Google is somehow complicit in it, they could just hire those people directly. And if it’s all covert operation, Israel is capable of training and coaching their spies to pass Google’s interviews. Google interviews aren’t trivial, but it’s also not some super-elite company which hires only the top 0.01% of software engineers.
If you want to convince me otherwise, you need to demonstrate why your explanation is more likely than the obvious one.
I used Claws Mail at some point in the past. Now notmuch+Emacs.