I think this is all that needs to be said on these articles.
(There's a lot more that _could_ be said, such as how few actual birthing HN readers there are, but I think the economics is really simple at the root of it.)
Besides, even the countries with really the worst outlook and conditions aren't falling all that fast. Russia since the high point of the 1990s: https://www.worldometers.info/world-population/russia-popula...
More relevant is something like Japan. [2] They are currently losing 1 in every 200 people, every year. And that rate of decline is still accelerating. And they have a similar fertility rate to Finland 1.37 vs 1.42. The only difference is that Japan has had its low fertility rate for longer, and so it's closer to the equilibrium rate of loss that such a fertility rate implies, while Finland is closer to their older higher fertility rates.
[1] - https://www.macrotrends.net/countries/RUS/russia/fertility-r...
[2] - https://www.macrotrends.net/countries/JPN/japan/population
Russia has lower fertility rate than EU average, at 1.50 vs 1.53. And a higher and faster growing share of Muslim population than Europe.
Overall, death rate is about 1.37x more than birth rate in Russia (999.14 vs 728.02 per 100K in first 10 months of 2023 - link to official stats https://statprivat.ru/demo2020?r=3). In EU it's 10.7 vs 9.5 per 1000 (in a full year), so only 1.12x the difference. Births are 8% lower per 1000 and deaths, 12% higher. Plus, Russia has a higher proportion of Muslim population than any EU country and it grows faster too, so for white population situation is beyond dire: in ethnic Russian majority regions apart from Moscow and St. Petersburg, death rate at 2.5-3x the birth rate is the norm.
If you've been under impression that Russia somehow has some sound demographic policy and/or family culture and is doing better in this respect than any European country, you're just a victim of Putin's propaganda. Compared to EU states, Russia is only better than Bulgaria in this respect.