Sorry, no.
All Environmental Impact Report/Environmental Impact Statement (EIR/EIS) have been approved between LA and SF with the exception of DTX between King and 4th to Transbay Transit Center in downtown San Francisco and between Palmdale to Burbank. The latter has Draft EIR/EIS that has a pretty clear strategy of maintaining 220 MPH (or close to it) mostly in tunnels under the San Gabriel mountains. So the strategy to reach the goal 2:40 is pretty sound^[1].
Now I would like to add that nothing here is a novel technology, there are plenty of build out systems worldwide with non-maglev trains maintaining a speed of 200 MPH or close to it, and even a handful of systems that maintain 220 MPH. The geography of the Central Valley even lends it self nicely to this with it’s flat surface and relatively straight lines between stations. The only novel thing here is maintaining a 220 MPH in several tunnels. However I don’t think this will be an impossible engineering challenge, and the EIR/EIS statements agree with that.
Also note that initial planning was for 200 MPH inside those tunnels, but after the preferred alternative of shared 110 MPH corridor between Gilroy and San José was approved, then it was decided to increase the speed in the tunnels to 220 MPH to make up the lost time. I think this was a good decision as you say, the challenges of building a fast corridor within city limits are probably greater then the challenges of going really fast inside tunnels. And as hinted the trains will only blast through caltrain stops at a max speed of 110 MPH, not 220 MPH.
I do want to emphasize the fact that the approved EIR/EIS has on the credibility of the project achieving its goals (this goes into concerns you raised in your other post). This means that interested parties had their chance to scrutinize every aspect of the plan, that includes engineering challenges as well as civic challenges (including right of way acquisition). I do agree that the property acquisition has proven difficult in the Central Valley (particularly around construction packages 1 and 2-3). This is in no small part down to the amount change orders and difficulty of utility relocations along the right of way. My understanding is that the authority has learned from these challenges and is now forcing its contractors to finish all the advanced design before they begin construction on that segment. This should significantly reduce the number of change orders which would make it easier to acquire the needed parcels.
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1: There is a case for the DTX to actually slow things down (I very much doubt the trains will be traveling much faster then 50-60 MPH this last mile), but this will only be like a minute or two. So I will give you 2:42 hours is actually a likely final number.