Not really, there's no time loss from switching to old graphics. Also doing the belt shopping itself is faster in old graphics because less mouse travel between belt and merchant screen.

Also some runners spam left click with new graphics as well and it's faster than belt shopping.

I didn't really test this that extensively, but basically in the new graphics you can't move your cursor even 1 pixel when doing the left click > enter sequence, so people swap to old graphics to avoid this.

I think this buying sequence is only worth it when you don't have the 3-row belt, after you get to act 2 with the 3-row belt I think filling your belt and dropping it will be faster than the other method (unless you have rejuvs on one of the lines as well)

So it would be faster for buying things like stamina, thawing, antidote. But belt drop would be faster in most other circumstances