As to who will use it and isn't it just for the rich, the train holds about 1,000. If the operators depend on it being full of rich businessmen on expenses, they'll be disappointed. Current fast trains manage, though slower routes or trains are available. But the current fare structure is complicated and often ridiculous; a ticket to Liverpool cost £125 single this month but only £25 in April, and yet that is for first class. Why first class gets a discount of £100 when, presumably, the traveller can well afford full fare is not apparent. And there are other curious results when buying standard fare, even on the day.
The Swiss manage with two classes and one fare for each, discounting by a set amount if the traveller is a frequent traveller who has their equivalent of a railcard. And their trains run on time, to the minute, and aren't overcrowded either.