No, probably not. Speak to any business owner who has been in a lawsuit and they'll likely tell you it's not worth the headache. A close relative told me that even if a customer straight up won't pay for a done job, he'd rather forgo the payment then deal with a lawsuit.
Lawsuits usually have:
1) monetary costs - those lawyers are very expensive
2) emotional costs - take a big mental toll to deal with
3) reputational costs - it goes in the public record. Next time a potential candidate googles your company, it might show up that you sued a former employee. Hopefully they read further to see if you were justified in doing so....
4) opportunity costs - you (hopefully) have better things to do with your time
If you are big enough, maybe you have a legal team to deal with this stuff. But even then, you have to choose your battles. A hired lawyer is still expensive and it's not worth going after small battles, even the ones you know you will win.
Also, as others have mentioned, it's not unreasonable to have a friend or relative look over your email communications during your interview process unless you were explicitly asked not to do so. In fact, it's a smart idea!
