Because Russia and her allies don't want to spend all their money on weapons.
For the price of a Javelin, they can have 20 Metis-M1 missiles... and if you look at experience in Afghanistan where the targets generally are not tanks... but often firing positions where the expensive Javelin has to be fire line of sight in manual SACLOS mode anyway the advantage actually lies with the cheaper, simpler and lighter Russian weapon... a weapon that can also be fitted with a thermal sight to use at night and in all weather.
Wouldn't heat seeking and SALH be much more efficient?
No. When pointing a SAM in the air at a plane you will hear a noise called a tone when the seeker is locked so you can fire your missile. You can be sure the aircraft is locked because it is the only hot thing up there, but pointing at ground targets unless you use a very sophisticated thermal imager you are not going to be able to tell what the IR seeker has locked on to... and most of the time the precise thing you want to lock on to might not have an IR signature that makes it stand out enough to get a lock... except Gas turbine powered tanks like the Abrams or early model T-80s.
SALH is not really fire and forget because someone has to point a laser at the target (and the Soviets and now Russians have tons of artillery shells guided by laser anyway).
The americans have a lot of experience with them like the hellfire, maverick, javelin(i'm not saying its good but it still is F&F) and while the Russians are superior in all other categories of missile building they are lagging behind in F&F weapons.
Really? If you are going to include TV guided Maverick, Laser guided Hellfire, and IR guided Javelin then what about TV guided Kh-29T, laser guided Kh-29L, Kh-25ML, Krasnopol, Kitolov, Gran, and indeed Svir, Kornet, Kornet-EM. Krisantema?
Hermes is going to have SALH, MMW radar, GPS, and IIR seeker options... and a 30kg warhead.
Do the Russian armed forces don't have the technology or they think that F&F AGMs and ATGMs are completely pointless?
They try to minimise the cost of the weapon system, so for instance they could have make Vikhr-M into a SALH missile, or indeed the Kornet, but they chose to fit the equivalent of a TV mavericks guidance into the platform, so the onboard TV camera is kept stabilised and pointed at the target, which is used to aim a low powered laser beam. The missile looks back at the launch platform and guides itself to the target so target mounted dazzlers or smoke have no effect and the missile remains simple and cheap with no expensive thermal sight or radar needed.
The real question you need to ask is who is getting the better deal... Javelin has a low spec thermal imager in its nose because it is designed to work for a few seconds only and then be destroyed. That means it lacks range and does not produce a great image limiting range. In comparison the Kornet-EM has a much better thermal imager in its sighting system and can engage ground and air targets out to 10km with a missile that is cheaper than Javelin. With its autotracker the Kornet is practically fire and forget in terms of what the operator needs to do.
I think the Russians are getting a much better system and they are getting it for much less.