Are you able to adjust its picture settings when it's in store mode?

No. Brightness and contrast are maxed out but it's not bad with a cheaper model.

My opinion --- in some cases, the difference between expensive and cheap boils down to the picture controls being intentionally limited for marketing effect.

So the cheap model maxed out looks like the more expensive model at medium. People can recognize the difference in the store so they opt for the more expensive one. But the actual displays themselves are virtually identical.

It may actually be cheaper to make one grade of display and differentiate using the controls.

What does store mode do?

It disables smart features and many of the settings making it more like a dumb HDMI screen.

This may seem like a good thing, but it also usually enables a "vibrant" postprocessing picture mode, motion smoothing, and maximum brightness so the display looks good in a well lit big box store. Unless your viewing environment is similar (or you don't care so much) that's probably not what you want.

Motion smoothing is awful.

I've always thought this feature might have more potential if more modern deep-learning tech was baked into the video and not just dumb frame interpolation.

I can imagine that there would be a potential to generate interpolated frames that intelligently make fast-moving scenes more understandable while leaving slow-moving scenes more or less at their intended 24 FPS.

Many action movies, especially with close hand-to-hand combat in tight spaces, are difficult to understand visually because 24 FPS just doesn't quite catch the movements.

It will happen, look at the results they are getting out of the framegen stuff on pc graphics cards. DLSS and friends.

I sort of don't like it(Old man shakes fist at sky "I want my frames to be real") but they are getting amazing results.

Depends on the TV. I prefer it off, but on my fancy OLED TV, there is too much "judder" without it on.

It also, in my case, puts up a giant info banner on the screen across the content, about the screen's capabilities, so YMMV.

This occurs on my model as well.

This is interesting to me. I never heard of "store mode". Is that common for "smart TVs" these days? My interest here is for my elderly mother who tries to watch TV, but her current LG is constantly bombarding her with notifications for software updates, recommendations and ads. It's very frustrating for her; it's to the point where she's afraid to turn on the TV.

I want a TV for her that will power-on directly to YouTube-TV, and that's it, nothing else, no notifications, nothing.

It lobotomizes the TV