The supposed threat was never from NATO or a threat to Russian security. It was direct threat to Putin's kleptocracy.
"The democratisation of Russia’s former subjects indeed represents a threat, but not to the Russian people. It is a threat to the Russia’s kleptocratic authoritarian regime.
Free and democratic nations ‘give a bad example’ to the Russian people."
"in 1989, over 315,000 US troops, which formed the main NATO military force, were permanently stationed in Europe. By 2014, when Russia annexed Ukrainian Crimea, their numbers had dwindled fivefold, to some 61,000.
Within the same period, the number of US military aircraft in Europe fell from 800 to 170, while all of its 5,000 tanks were returned to the US.
Overall, the US military presence in Europe by 2014 was only 15 per cent of its size in 1989.
European NATO member states also reduced their military forces after the end of the Cold War; by 2014, the average military budget was some 1.6 per cent of GDP. In the meantime, Russia was intensively modernising its weapons and reforming its military forces with military expenditure of between 3.2 and 5.4 per cent of GDP."
Article -
https://balkaninsight.com/2022/06/22/the-truth-behind-the-myth-of-russia-threatened-by-nato/