I'd like to know the rationale behind these weird timezones, in particular non-hourly offsets to UTC. Why was it chosen that way? Why is it being upheld? It must be a big hassle.
Why not switch to a normal 60 minute offset to UTC?
tzdb often has the answer, and it's almost always because everyone used to do local solar time (i.e. on average, the sun is at the top of the sky at noon) until convenience (i.e. train and plane schedules) required an offset friendlier to mental math.
Why not switch to a normal 60 minute offset to UTC?