Slovakia air defense compared to Serbia air defense

Land locked sexy Slovakia
pop: 5.4 million
can muster 4 (out of 8) MiG-29
7 L-39s (4 upraded)
4 Lets
10 Hips
2 Hops
5 UAVs
4 Sa-6 batteries
1 S-300 battery

But
Land locked sexy Serbia
pop: 7.2 million
14 MiG-21s
maybe 15 oraos
2 an-26
1 an-2
12 g-4?
5 lasta
9 hips
unknown number of gazelle

how come Serbia can’t muster like Slovakia