He (janeczku) is right and pretty much everyone agrees they were descending way too fast (for whatever reason).
The normal (green) path angle is tg-1 (300/6100) = 2.8 deg
The path they took is (at the very least) tg-1 (400/5000) = 4.6 deg
It does not even matter much if the 400 m alt reading at 10:39:59 is barometric or radio as the ravine is not starting yet. I said "at the very least", because at the outer marker they clearly were above 400 meters.
Which is why the "new crew" in Poland (that is the young guys from the 36th regiment plus the brother of the dead president) scream that it is all Russian ATCs fault because he was giving them the "on course, on path" readings. At the same time, the "old crew", which is the older guys who were trained in Russia say it is pilots' fault because they were using radio altimeter, autopilot way below 100 meters limit that is called for by the Tu flight manual, had no simulator training, etc.
Which leads to the question (as everyone here already asked) why was the ATC giving them these confirmations. The ATC claims in the interview his radar equipment gave him no independent verification of the altitude, which means that his "on path" confirmations were either complete BS or were based entirely on the altitude reports he was getting (for a time being) from the plane. If this is what indeed was going on, then RA altitude received as barometric altitude could indeed lead to "on course, on path" confirmations. He did complain from early on that the crew was not reporting altitude to him often enough and possibly had "problems with numbers".
And that pretty much is where this matter stands as of now.