Orange killed off services soon after France Telecom came along by degrading the service, stopping support, taking ages to fix problems or downtime, never advertising it ... and then used the classic 'no demand' line to kill it completely.
I've heard loads of bad things about TuGo, and fortunately the system used by Three - and also being trialled shortly by EE - don't work the same way (even if they essentially do the same thing). I believe one or both will use new standards for carrying voice over Wi-Fi, which is a step closer to Voice over LTE - which will enable voice over 4G. Once there's no need to ensure 4G doesn't extend beyond the coverage of 2G or 3G, the power can be 'ramped up' to vastly improve coverage and service in rural areas - which will also have a definite benefit to rail users too.
Most of this will probably not happen until this time next year, or even the end of next year, but it will happen and eventually 4G coverage will be as good, or superior, to that of 2G. So you'll finally have decent data access everywhere - not 2G that's pretty much voice and text only, and patchy 3G.
Ultimately, it would be great to see 3G (and not 2G) 'refarmed' for use as 4G and 3G is axed completely. There are many users and embedded data systems relying on 2G still, but 3G is easily replaced with 4G (if you consider doing it in 5-10 years from now, not next week!).