Ps2's dominance definitely gets mythologized a bit. Don't get me wrong, it was an absolute HOUSE, but by the time the ps3 actually launched, the ps2 was lagging behind the ps1 (though, regionally, it had made significant gains in the US) and somewhere around 97 million sales. It also was uncommon, but not unheard of, for the gamecube version of a multiplat to outsell the ps2 version. It got a bit of a long tail due to the ps3 famously shitting the bed, but the majority of those remaining sales were made in 3rd world countries that were just adopting dvd as a format for the first time, and the ps2 was the cheapest dvd player on the market, and software attach ratio plummeted after that point.
I think realistically, the actual sales of the ps2 are somewhere between 147 million and 150 million. Sony hadn't really updated the ps2 sales for a few years, but all of the sudden, dropped multiple years at once as soon as the ds was creeping closer to the ps2's at the time total of 145 million. Sales were averaging ~1.2 million per year according to those figures, and pretty steadily dropping year over year. Suddenly, a year later, sony drops the infamous 155 million number. According to them, the ps2 had gone from selling 1.2 million a year in the twilight years of its own successor to selling over 5 million in a single year. This totally had absolutely nothing to do with the ds barreling past previous estimates in the wake of the rough launch of the 3ds. And then in 2024, sony "updates" the number, and rather than doing the sensible thing of saying "The ps2 sold an additional 5 million in the decade since we previously updated the figure", they unironically go with "Actually, we miscounted, it really sold TEN million that year!"
Mark my words, I think they did this in such a way so that if the switch 1 looks like it will pass 160 million, they have room to say "Oh, the ps2? The total is actually 165 million, there were some regions still selling it as late as 2017, like India!"