They’d help guard against dust getting to the cards but would do very little protecting against air/moisture because the zipper isnt an air tight seal. If your going the binder route, the only surefire way to prevent air/moisture getting to the card is double sleeving. IMO finding an inner sleeve that fits your cards nicely + Dragon Shield/KMC Super Series for the outer sleeve. Plus leaving your double sleeved cards under a Webster’s Dictionary for 2 to 3 days to squeeze trapped air out before putting them in a ringless binder is the best route.
Best Ringless Binders aka Portfolios (Dex Protection/Dragon Hide by Legion/QuadRow) - matter of preference but DeX/Dragon Hide are far and away the best.
Best Inner Sleeves
Toss up between KMC or Ultra Pro Perfect Fits (I have yet to find a perfect fit brand that consistently isnt too tight)
Best Outter Sleeves
**#1** KMC Super Series - Easily fits around sleeved card
Dragon Shield - Frustratingly hard to fit around sleeved card. Putting a regular card ontop of the sleeved card then sliding both in and taking the regular card out works but is very time consuming.
I’ve been using these the Pro Index System since the early 2000s. I bought a Neo Destiny set in August 2018 that was heavily warped. Here’s what they look like now.