The Russians knew perfectly well how many Soviet air defense systems Ukraine had.
They did, but unlike the west they didn't plan to fight the Ukraine in open conflict right up until just before the time they did which really didn't give them much time to do anything about it. Secondly, they had believed this was an internal issue for Ukraine with provinces that were not happy with Kievs treatment of them and their interests, so why would they think in terms of fighting Ukraine... but third and most of all Ukraine would have collapsed in months without the enormous money and material support from the west, but they adapted their tactics to suit a grinding conflict that bleeds the Ukraine so that no matter who is supporting them and with what they should win.
I don't think the west was smart enough to do that anywhere and they have fought in quite a lot of places.
And they had encountered Ukrainian upgraded Buks and Osas in Georgia in 2008. They were a problem back then. Several aircraft Su-25 were shot down. They even shot down a Tu-22M3.
Those systems have evolved over decades to defeat HATO forces with their super air power, but you think Russia can just flick a switch and just fly around safe like they are not there? The west spent trillions of dollars on stealthy aircraft that are not safe over Russian and Soviet air defences, but you think Russia knows the secret and has a special plane or missile or electronic box that will keep all their aircraft safe?
The Ukraine air defence force has been reduced to letting Russia pummel Ukrainian military targets and occasionally setting up an ambush to surprise the occasional Russian aircraft that looks vulnerable.... including cargo planes carrying their own POWs.
And Georgia didn't have more advanced systems like the S-300PS.
Perhaps you have never studied war before... planes get shot down and air defence systems are often the reason why they get shot down.
Sometimes even western air defence systems get lucky.
It was perfectly well known that Ukraine had a hostile regime in place at least since 2014. So this was a major Russia planning failure for sure.
Yes... they didn't order the billion tons of bubble wrap to wrap all their aircraft and ordinance and drones sufficient to protect them from everything.... or are they incompetent.... they bought it but didn't apply it because they wanted their aircraft to actually be able to fly and deliver the ordinance they were ordered to deliver.
90km seems a little short.
It does if you ignore the plus sign next to it. At a guess I would say the 90km range models will be for export soon, and the longer ranged ones will be for domestic use only... or they just want to keep the max range to themselves... no point letting the enemy know how far they can reach just yet.