It's just a pity that the UK (and also Ireland although the population density there excuses it somewhat) didn't put more investment into electrification of railways.
Seems daft that the governments are pushing sustainable energy policies while railways are operating significant numbers of trains on diesel instead of electricity.
Rail is the ideal platform for electric transportation and realistically all but the most underused rural lines should be electric.
Diesel Intercity shouldn't really have ever been necessary in Britain on busy lines.
In France and elsewhere that's the case because they've access to abundant locally generated power and they use it for ensuring they've alternatives to petrol, diesel and aviation fuel where possible.