It probably gets 95% of the calls right. FIFA says 99.3% but I don’t think so. Still, if it didn’t exist everyone would be crying to implement technology like they did before. Think of all the goals/no goals that have been rightfully overturned. Even if there are some horrible calls sometimes, the good calls outweigh the bad ones.
All audio and replays should be made available. Don’t know why they tried to re-invent the wheel when other sports already have an equivalent system that they have honed over the years. Rugby still has controversies but at least the discussion is open and the decisions are clearly communicated, also they show a whole clip of an incident instead of one screenshot of a tackle for example - context is important (mitigating circumstances). Also like the use of the yellow being a ten minute ‘sin bin’ with option to upgrade to red but that’s a different discussion