Regarding the shackle bolts freezing up, the effect of that is directly related to the suspension travel. The more the springs compress, the more important it is. If they don’t rotate it serves to partially bind the spring. IE, it more important the softer the spring or bigger the lift/ arch of the spring. It’ll spin between the bushing and sleeve for a while but the silicone lube is just for installation purposes. Silicone doesn’t last long( and doesn’t degrade the rubber). That’s why higher quality connections have greaseable bolts.