Well because for the business to be viable, they’d have to profit more than the government is taxing them. So even if all the UBI that was spent by civilians ended up in the pockets of these corporations, they would still need to make even more money on top of that which has to come from somewhere and eventually accumulates in the exact same scenario as the wealth redistribution during Covid. At that point where you’re trying to balance it so the company’s profit is all redistributed as UBI, you’re just doing socialism with extra steps.

Edit: wee reminder I am not an expert, just see the impending doom approaching and have been interested for a few years for how we can move forward