The way you have to see this story is that it came right at the tail end of this entire trend
The "childhood friend cheats on the MC with the NTR boy, MC is saved by the Real FMC, and the CHF and NTR boy get their lives destroyed" setup is a trope that, while not exactly new, really took off in the WN scene around 2018 and continued full force up to 2022-23. That's why we're seeing so many of these adaptations lately, with the manga industry trailing behind as they get adapted.
I personally read over 30 of these back then because I was bored, and some of them were actually kind of funny in their execution (My favorite because of how overblown it was is one where the Real FMC planned 10 years ahead, making sure she and the MC ended up well-off while the cheating pair had their lives ruined. She even planned dates in specific places and times so the NTR boy, who ended up as a wagie, would see them dressed up and having fun while he left work miserable. That pushed him to cheat on the CHF (who he had married because his family found out she was pregnant and made him take responsability) with an underage girl and land in jail (Well, this part was purely the NTR boy's actions). Then the CHF, a single mother now, finally realized the pain they had put the MC through all those years ago, since the NTR boy's cheating genuinely hurt her and yada yada. The final scene years later shows the CHF and her daughter crossing paths with the real FMC, the MC, and their child, with the MC not recognizing her, and she ends up crying. And the funny thing is all this happened without the MC knowing, as he had actually made peace with the situation and the CHF long before, so it was the Real FMC going "yeah no, fuck them, I will make them suffer")
And right at the very end of this entire trend, you have this story, which takes all the plot points that make this kind of narrative appealing to read, mainly the revenge, and turns them up to eleven.
That's why it feels so overblown. It's like seeing the final escalation of a genre that kept trying to outdo itself. It's the ultimate revenge porn at the end of a long line of revenge porn.