The existing track corridor in New England is not appropriate for true high-speed train service. That really requires new right-of-ways, which would be extremely expensive in the Northeast.
There are currently plans for the next version of Acela but it is more about replacing aging equipment than any true speed upgrade. The Acela trains are almost 20 years old but I've never been on one as the price difference from the regular service isn't worth the small increase in time. Here are some numbers. I'm showing the cheapest "Saver" fares which are limited, must be purchased in advance, and have strict refund rules. I just picked November 4 as the date for advanced purchase (about +30 days):
NYC to Washington DC.
Acela Non-Stop: $137, 2h37m
Acela Regular: $137, 2h57m (+20m from non-stop)
NorthEast Reg: $54, 3h25m (+48m from non-stop)
Here are Boston to D.C: Acela Non-Stop: $144, 6h39m
Acela Regular: $144, 7h5m (+21m from non-stop)
NorthEast Reg: $81, 7h59m (+1h20m from non-stop)
Everyone swooning over the train infrastructure in China seems to overlook the raw power that the Chinese government wields to claim right-of-ways, fix labor rates, and so on. It is also almost impossible get a good sense of the financial structure of those projects. How much money was put into them? Could that money have been better spent elsewhere? What is the debt structure? The ROE? The environmental impact?