Well, the comparison of cold, hard operating metrics you so conveniently left out in the quote, for example?
I suppose you meant this?
1 million passengers sounds like a lot, but for an aircraft that entered "service" 4 years earlier and numbers 33 active airframes that is in fact a dismal performance! Take for example the SSJ100, itself not exactly a resounding market success and beset with spares shortages which affect daily utilization rates. By October 2020, one single airline (Azimuth) operating 12 Superjets had managed to transport 2.7 million passengers since starting service in late 2017 and for 2021 alone, it aims to hit 2 million! In other words, 170% more passengers in 75% of the time, using 64% fewer aircraft - the ARJ21 has achieved little more than 10% of the passengers per aircraft and year. And that's compared to an aircraft that is by no means the best-performing candidate in this respect.
Well, first of all, from Hendrik's post it's 1.5 million passengers, not 1 million (The youtube video is a bit dated). From Wikipedia, the number of active ARJ-21 in operation is 48, not 33 as you have so conveniently quote with a lower number again.
The bulk of the increase in the number of passengers and active aircraft in operation comes from the last 2 years, which include 2020 where traveling by air was banned for almost the entire year.
That's why there's bound to a major distortion if you compare these figures with those of the Azimuth where passenger traffic was more evenly distributed in the number of years since in operation and production/delivery of the Superjet was already in full swing.
The production rate of the ARJ-21 is now at 30 per year, which is over 50% of the total number of ARJ-21 that has been built (52), and that is in just ONE year.
There's bound to be an exponential increase in the number of active ARJ-21 in operation and the number of passengers in the coming years especially if they manage to get the pandemic under control and air traffic return to normal.