The more rail improves the more I'm tempted to take it, with flying you have the additional time cost of just dealing with the airports, turn up an hour early, then get put in the metal tube where they won't serve you drink till they're up in the air, and you can't bring your own.
A train may take longer sometimes, but I find the whole thing much less stressful, you're not strapped to the seat, you have leg room, even a table, power sockets, bring your own food and drink, and the prices are competitive.
It still takes longer than I'd like to get from Switzerland to the UK, and that's mostly due to a lengthy change in Paris.
I think in France, and prob other countries too, their moving to ban domestic flights that can be done on rail instead