Which doesn’t fit Arminianism.
Whereas on the other hand, the other traditional (Calvinistic) interpretation puts all responsibility on Satan, leaving God surprised that it happens. Which doesn’t fit Calv notions of God’s sovereignty at all; and those actually in the kingdom shouldn’t be hopelessly lost if Calvinism is true (although Arminians would interpret that as meaning someone actually in the kingdom can hopelessly lose their salvation. But not for anything they did, only for what they couldn’t help being, which goes back to Calv theology again.)
When I see a weird mix of details like that, I tend to expect from experience the parable is more about warning people who think they’re servants of God that they had better watch out, and less about teaching some us vs. them scenario.
And on one harmonization theory, Jesus had switched over to this parable after Pharisees had been willing to violate their own principles to declare that the concept of God saving someone whose latter state is worse than his former, is of the devil. That’s the poison being analogically condemned here, with threats of punishment.
But the disciples weren’t getting it yet, either, or they wouldn’t have had to have the parable explained to them: an explanation that turns out to have serious problems for any theory of hopeless damnation, even though on the surface it appears to be evidence for it. But whatever the parable was warning about, its obscurity to the apostles meant they were actually on the side of the darnels! But that was hardly a hopeless condition for the apostles.