You're right that that's a generally better version.
However, for these trains running on existing rails through large rural areas without electrification, on existing rails meant for diesel trains, they'd have to either retrofit large amounts of track. Biggest issue is power. Electrified rail needs solid power grids to regularly get power from. If you have long distance power lines overhead, feeding from only one location, the power would need to be very high voltage, and would need large transforming stations to step it down.
If you build generation stations to get electrified grids, you have to figure out how to get reliable energy on demand to supply the train, which means a lot of green energy sources are unfeasible without batteries or another storage method. If you do nuclear, its extremely expensive. If you do fossil fuel, it may as well be diesel. So green energy is probably the best option, but its also pretty overkill unless other grids exist in the area to take advantage of the new power plant, and if it relies on energy storage, it has the same losses that just using energy storage on the train has, and there'd have to be storage at every plant, instead of just one storage on the train.
Its hardly an unfixable situation; several of the other options I listed above certainly could work, but at a glance, without knowing the exact situation, I couldn't tell you which would be best. I certainly don't know if hydrogen fuel is better than making electric rails work. But I guess time will tell whether China's engineers picked a workable solution or not.
You're right that that's a generally better version.
However, for these trains running on existing rails through large rural areas without electrification, on existing rails meant for diesel trains, they'd have to either retrofit large amounts of track. Biggest issue is power. Electrified rail needs solid power grids to regularly get power from. If you have long distance power lines overhead, feeding from only one location, the power would need to be very high voltage, and would need large transforming stations to step it down.
If you build generation stations to get electrified grids, you have to figure out how to get reliable energy on demand to supply the train, which means a lot of green energy sources are unfeasible without batteries or another storage method. If you do nuclear, its extremely expensive. If you do fossil fuel, it may as well be diesel. So green energy is probably the best option, but its also pretty overkill unless other grids exist in the area to take advantage of the new power plant, and if it relies on energy storage, it has the same losses that just using energy storage on the train has, and there'd have to be storage at every plant, instead of just one storage on the train.
Its hardly an unfixable situation; several of the other options I listed above certainly could work, but at a glance, without knowing the exact situation, I couldn't tell you which would be best. I certainly don't know if hydrogen fuel is better than making electric rails work. But I guess time will tell whether China's engineers picked a workable solution or not.