Corrosion, in almost all circumstances regarding a pool, is dominated by pH. Salt has almost nothing to do with it and people that report corrosion are often not keeping their pool water correctly balanced. And guess what - any pool using chlorinating liquids OR stabilized solid chlorine products is a SALT pool. Muriatic acid also adds salt (chloride) to your pool water. It is not uncommon for pools that run all year to have their chloride levels go up by a 1000ppm/year. Chloride only enhances certain forms of corrosion (like crevice corrosion and pitting), it does not cause corrosion.
Intex pools, relatively speaking, are cheap. They are not manufactured from high quality materials and the metal frames probably do not use high grade steels. That's the point, they are affordable so they must be built with lower quality components. I very much doubt the frames are powder-coated but likely simply spray painted. That would have significant impact on corrosion resistance. The presence of salt water (at levels 10X lower than seawater), will not change that fact.
In a metal frame pool, the biggest driver of corrosion, aside form pH, will be galvanic corrosion. If that is a concern, then one can simple purchase a $10 zinc sacrificial anode and bury it in moist soil near the pool frame. Connect the anode to a bare spot on the pool frame using #8 solid copper wire and it will protect the frame from galvanic corrosion.
If you want to use a slat-water generator, I suggest you go for it. Most of the information out on the internet regarding SWGs, salt, stone damage & corrosion is just simply wrong. With over a 100,000 TFP members, many of which running salt pools, if corrosion were such a huge issue, we'd know about it. Right now, saltwater scare tactics are being heavily used by the pool building industry to push people towards "alternative sanitizer" (UV, ozone, minerals, etc); don't be fooled by the hype.