Display Moremost of this is based on asumptions, and I don't get the power imbalance thing either, it is really hard to find a couple who is exactly balanced in their career and life
What about Taeyeon and Baekhyun they dated with a 3 year age difference according to Baekhyun Taeyeon was a mentor figure to him also obviously under the same company
so huge power inbalance by your standards
I mean even my parents who have been married over 45+ years had power imbalance since my mother still studied when they started their relationship also what about stay at home mums there is even a bigger power imbalance there
it would be of course different if one of them was the other's supperior/boss or has major bearing on the orther's career but as far as I know they weren't even in the same company
He debuted like 11-12 years before she was going viral and while Taeyeon and Baekhyun was a little imbalanced too considering they were in the same agency and she was a little older and more successful too, it was a little less bad then Hani and Junsu because Taeyeon was the one being hated on by fangirls (and it was obvious that this would happen) while Junsu's fangirls hated on Hani and Taeyeon was less connected, had no power outside of her group in SM and they were a little closer age wise.
And you can't compare someone studying and someone working being in a relationship together to this. Your parents situation would only be similar if both worked in the same field with barely any employers, your father would have to have a senior position and would have to be well connected to other seniors. Also, at some point such a "power imbalance" disappears but it is still critical when it is happening right now.
Considering TVXQ had insane fans it was also irresponsible to date someone, who has just found fame and not wait a little bit at least. As the older part who was popular since years, he should have known it is not a good idea to ask her out that early (just one year after going viral). And sure Hani was 24 but she was rather new to being famous especially since female idols get more hate then male ones. And I personally think a 24 year old and a 29 year old are in different life periods most of the time so it is a little iffy. And yes I know most don't see it like that but I know so many couples with that age difference and around that age and you do notice a different maturity level (even if the couples themselves does not notice it). Especially in the 10s and 20s it is extreme, if it was for example a 28 and a 33 y. o., there would be less problems or if she would have at least been famous for min. 4 years. She was basically considered a rookie dating a senior idol from a legendary boy group.
And yes, stay at home mums have a problem because most can't really leave their partner when they stayed home for years, the employers think they are not up to date anymore and because of this "cost" to much time to employ and teach them. 3 years without a job is often (depending on the branche) a critical k.o. criteria for employers. And unless the stay at home mum gets (pocket)money, she is depending on her husband for financial matters and has in a lot of cases trouble to move out should the relationship go wrong unless friends or family let her stay with the child(ren) or lend her money.