Public companies have a responsibility to their (rational) shareholders to minimize expenses that have no possible ROI. Taxes are chief among those.

If you're asking for my opinion, in my opinion what he is saying is absolute nonsense. The populist drivel spewed in those tweets is an attempt to appeal to his Shark Tank audience. If he appears relatable, the show's ratings rise and he gets the accompanying ego boost. He's doing it for the same reason that centimillionaire Hollywood types advocate for socialist candidates & ideals that are in direct conflict with their own financial interests: popularity.

Any company that has options available to it that will lower their tax bill without negatively affecting their income and growth prospects should pursue them. In fact, they have a legal responsibility to their shareholders to do so.