Hmm, what I got from that is perhaps you have become cynical to romance, at least in Western Animation, and feel that it can't be done in a 22 minute episode?
Cynicism is believing that people are motivated first and foremost by their own self interest.
I am tired of animation, live action, TV, movies, etc presenting an unrealistic view of romance with such regularity that people believe it. A better word than "cynicism" is "indignation". Romance CAN be done in a show that is only 22 minutes, but it is VERY hard. Healthy romantic relationships don't develop that fast, so you have to come into an existing romance, like "canterlot wedding", or an existing strong friendship that is evolving, or you have to develop it over many episodes. Shows and movies keep abridging the process to make it fit in their medium. It is lazy and destructive. And I am tired of seeing people act in real life the way they learn in these movies. For most, the best they can hope for is an unsatisfying relationship, and at worst people get hurt by it. There are tons of anecdotes about it working, but these are the exception, not the rule.
It should be noted that nothing came from the love triangle and that this is the second time Rarity crushing on a stallion has not blossomed into romance. Which really proves a realistic point, that crushing/wanting a relationship with someone before even meeting them rarely works out.
I would say, in the case of Rarity, romance has been handled well. Though at this point I feel she should be given a break. The mare wants romance and to find the stallion of her dreams, give her the chance of finding this without crushing thoses dreams.
I disagree that it was handled well.
This is at least the second time that Rarity crushed for someone without learning the most important lesson of it. This episode was NOT about crushing being unrealistic and silly. It was about not changing who you are. Basically saying "It's ok to crush, just be yourself while doing it".
This is cosmically missing the point. If the whole episode was about being yourself, then they could have executed in a way that wasn't relationally distracting and harmful. For instance, Rarity could have so wanted Trend to be a friend, that she could have changed the theme on his every half backed whim, crippling the project until she went back to her plan.
If the show was supposed to be about crushing being silly, then they failed horribly by losing track of it in the final critical minutes.
Rarity wants to be married...but why? What is her motivation? It doesn't seem that she wants a partner. She seems to want someone to put on a pedestal. She wants to live in a fairy tale. Neither of these could be satisfying to her long term. She needs to fix her self esteem, and then look for a partner. Someone who will appreciate her work and be her equal.
You are using the same vocabulary I'd expect Rarity to use: "stallion of her dreams".
As long as it is fantasy, she has something to learn first. I want her to one day figure it out and to get into a healthy marriage. I do NOT want her to fall blindly into a doomed relationship, have a hasty wedding, and then struggle the way I see people.
A healthy relationship has a few more pieces:
1) uninformed optimism (you like them, but don't know them well enough to understand who they are)
2) informed pessimism (you know their crap)
3) crisis (you have to deal with their crap)
4) informed optimism (you know you like them, and why, in spite of their crap)
I don't want Rarity to get hurt unnecessarily, and I don't want her actions to cause real people to get hurt.