Maybe between £50-60k per annum perhaps more in London. Its a demanding job with drivers having to know the track, curves, braking points etc inside out. Seems a fair wage all things considered.

The salary is also an indicator of what good union representation does for the worker.

My preference regarding train strikes would be how the Japanese approach this. The bus drivers went on strike, carried on working but refused to collect fares. The passengers weren't impacted and therefore support for the drivers was overwhelming. The owners were hit in the pocket and quickly acquiesced.