Imho western side is lacking in coastal def missile systems. Russia doctrine made them pushed the R&D on missiles base system including coastal. This is also true in terms of Submarine technology, tho they are now getting left behind abit in this area. But to underestimate overall Russian Submarine technology and missiles defense system is surely a foolish move, as those two are they pasopati kinda weapon. US build carrier-Russia build Submarine, US made great jet fighter-Russia made great missiles, for themits all about balancing the power.
On the other hand US doctrine which bring war as far from homeland as possible making them lacking in missiles air def system (not being prioritize). Perhaps one of the reason why they bought one from Israel. But dont get me wrong, lacking in this case doesnt mean its bad.
I personally like Bastion/yakhont coastal def system, and I did read some open source materials on S-400 complete system due to my curiosity. On paper S-400 really something that the west need to be reckon with, its going to be a pain in the butt to jam it thats one thing.
But as good as the Yakhont/S-400 can be, at the end of the day its how it can integrate with other systems for force multiplier. Looking at the current choice of our preference to link the western alutsista those S-400 cant do much as stand alone system (tho it can do it). As much as I like them, I would prefer missiles def systems that might be less powerful on paper but can be integrated to other assets that we have