Have there been any blind tastings for that? I mean, if people swear by beef tallow's taste, they should be able to also prove it experimentally.
This would also set a level field between beef tallow and other oils. I would expect that a lot have changed in the fast food industry supply chain since the "good old days". Frying oil is only one of the factors that may have affected the taste of fries. Not to mention that everything tastes better when one is young.
It was very noticeable when McDonald's switched over. They were the first domino to fall.
I assure you if you'd been alive and consuming fast food french fries before and after the change you wouldn't think a blind test was required. The difference between whatever the hell McDonalds was using before the switch and after was jarring.
The difference wasn’t subtle, and they cooked differently after the switch, too. Plenty of folks had the experience of noticing that they’d had a run of bad batches of fries before finding out the recipe had change (so now all batches were bad) and effectively did do a blind taste test.