Yes, but with our current knowledge, we can only do our best at drawing the line of sentience. With what we know of plants, we can safely conclude they are not.
If that knowledge changes someday to point at plants being sentient, then we can redefine what is ethical.
There is no such thing, with our current knowledge, as plant suffering. And that's all we can base our opinion and ethics on. The hypothetical that plants may suffer is irrelevant in ethics discussions until we have any evidence that they do.
Capitalism does not work because companies will always seek to grow more and more and more. It's the core of capitalism. You need anti-capitalist policies to keep companies small.