[Gorshkov]

It is not about "how", it is simply about "those SAMs can engage sea-skimmers or not". In reality they cannot at all or can do that very poorly but it seems in Harpoon 3 with some databases they can shot down them very well. Plain and simple.
No testing is needed to be certain that something is wrong because no penalty flag during engagement of targets at VLow altitudes is known fact at that point. Tests can only confirm that more precisely. What I mean is to check which databases include "no-penalty flag" for those SAMs enabled and test them first time only with penalty flag enabled/disabled and maybe later second time with adjusted Pk (SSPK) according to reliable sources if they are available and first results won't be satisfactory. I do that as soon as I get Ultimate bundle because it is not much work as I suppose (several Russian SAMs I mentioned earlier, Chinese SAMs are mostly Soviet clones and most modern indigenous systems are of course capable of shotting-down sea-skimmers, Western stuff is much more numerous so I will look at it later).

Of course it is necessary to eliminate such ridiculous situations like invulnerable against Harpoon and TASM strikes Sovremennys, Slavas and Kirovs in 1980s scenarios.