I guess its hard to shoot them down as they fly low and do untargetted over borizon fire before running back woth tail between their legs. That goes for both sides, but i seen more helicopters lost when they were stationary

Likely lots of factors.

• so many shot down there are fewer to fly
• sanctions hurting repair channels meaning they fly fewer hours to reduce maintenance demands
• longer range Ukrainian missiles exceed the useful operational range of helicopters so to use them they’d have to station them inside Ukrainian missile range
• Lack of trained pilots? We know that Russian army trainers were put to the front lines (and liquidated), it wouldn’t surprised me if this was also done to helicopter trainers so now that they are dead the pipeline for new pilots is drastically reduced.