MolaKule has weighed in several times on this and confirmed there are no negatives to Lubegard Red, and it is one of the only additives or oils I’ve seen him recommend- and Lubegard Red is even approved for use by several OEMs. It’s the Lubegard Black & especially Lubegard Platinum that affect FMs & shifting.

Automatic Transmission Fluid Protectant - Lubegard

"LUBEGARD® Synthetic Automatic Transmission Fluid Protectant is a concentrated additive package infused with superior seal conditioners and friction modifiers. This unique product restores additive content to used ATF and enhances new ATF resulting in improved performance and smoother, more consistent shifting."
"Softens and modifies harsh shifts making them quicker in duration"
To me, those statements indicate some impact on the frictional properties of the fluid. Some transmissions may respond favorably, others may not. I see no reason to add these types of snake oil.