I don't know why the Unions are so keen for nationalisation. The fragmentation of the railway has allowed them to play one company off another. It's estimated that drivers wages are now a third higher than they would have been under BR.
But I suppose there is an ideological commitment to nationalisation and maybe they hanker after the ability to call national strikes against one company. Outside London most strikes don't get much coverage and seem to be a bit patchy.
The recent FGW strike was too bad for me as a passenger, getting back from the Southcoast I was a bit worried but the Virgin cross country was unaffected and I was mentally preparing for a trip from Reading to Windsor via Staines and a cab to Slough, but getting to Reading all I discovered was some branch line services cut back and some consolidated local and express services, so no big deal for most journeys.