That's what Mushoku Tensei does the best. People are so focused on Turning Point this and that, but that's not all it does.
Most people cringed over the moments of happiness shown by Rudeus until now, because it probably was a bit much for some, like the threesome.
But with this, all those "excessive" happy moments are shoved in your chest and you felt all that — with cringe and all.
This makes Nanahoshi's jealousy and pain feel even more real because Rudeus was the one that made her open herself up to have more friends, like Cliff and Zanoba even.
With this, she has been noticing firsthand Rudeus' happy life, this world's happy people, and all of that was denied to her.
This wouldn't have worked 10% as effectively if all those moments were not sent to the reader directly.
More than telling you that Rudeus is happy and Nanahoshi is suffering, when the story makes you feel it directly, the impact is way bigger.
That's some good writing...
And we are just getting to the middle of season 3...