That these are being “built” is once again a bit too strong a statement—the rail lines were already there and in use for cargo and the occasional suburban train. (The veeery slooow speeds at which the latter went between the big stations had relegated them to the sole use of urban arcanists and the occasional exhausted hiker disembarking from his long-distance train.) There’s some renewal of the aging rails, to be fair, and the stations are new.
Two problems with these:
First, the stations are too few and once again too far away from anything else. (Nobody’s fault—the rails are sometimes a century older than the metro and the outward creep of the city limits.)
Second, unlike on the ring, the trains on the chordal lines (I refuse to call them “diameters”) are operated according to the railway rules, meaning there are too few of them to be able to disregard the schedule, the schedule itself is at best a suggestion (and woe is you if you don’t keep track of train cancellations), and the stupid multi-hour midday “maintenance breaks” are still in place.
I’ve used these lines for weekly commutes, and if they fit your problem well, they can be very useful. But overall I’d say they are even more situational than the ring, and it’s frustrating compared to my utopian headcanon of how well they could work. Or hell, to the RER lines in Paris, even if those connections are no joke either—nevermind the Barcelona Rodalies, which are (or were, two decades ago) the platonic ideal of suburban/urban rail transport interconnection.
I, too, dislike the new connections, and the lack thereof, but the speed with which the new lines sprung up is a marvel.
I don't think it is possible to be physically unable to enter the train in 2023 (unless football fans return from thei match). In 2003 it was expected.
The other new ring is a fairly old preexisting train line that used to be cargo-only; it had the potential to be great, but unfortunately the ridiculously long connection times have made the real thing somewhat niche—if both your origin and your destination aren’t on it, the ten to fifteen minutes’ walk will likely make the result worse than just going through the center. And two connections are just never worth it.
(There’s a whole story behind how building stupid useless connections came to be viewed as a virtue in Moscow transport planning—look up “Vykhino effect”. Doesn’t make the result any less shit, though.)