If you're interested in discussing a rules-based solution, please proceed. If I wasn't clear enough already, allow me to be very clear now: I'm not interested in answering your question.
Fair enough.
To summarize my position regarding a rules-based solution: I interpret the rules as leaving it up to each DM to decide whether a particular climbing complication shares enough qualities with the example complications to make it reasonable to call for a Strength (Athletics) check. Mostly my interpretation is based on the inclusion of the text "At the DM's option..." but my interpretation is also influenced by the practical observation that the DM is the only one available to make that determination. I think it is unlikely that the designers intended to further restrict the DM's discretion to compare a particular complication to the example complications without including additional text to do so.
Ultimately, I think that if that a DM has identified a climbing complication they think is sufficiently similar to the example complications, the rules say that DM can call for a Strength (Athletics) check. Ergo, even though I would personally not call for a Strength (Athletics) check to climb an 80' rope, I think the rules give the DM the option to do so if they personally identify the height of the climb as a complication sufficiently similar to the examples in the book.
I know you disagree with my interpretation, and that you instead interpret the rules as never allowing the height of a climb to be a complication sufficiently similar to the example complications as to permit the DM to call for a Strength (Athletics) check.
I assert that I do not have a stake in the resolution of the question of which rules interpretation is stronger. Therefore, I do not believe I am engaging in motivated reasoning. As I do not have perfect self-awareness, I concede that it is possible that I have a stake in the resolution of which I am unaware. However, as you have declined to discuss the evidence on which you are basing your claim of motivated reasoning, I have only my own self-awareness to go on.
Similarly, I assert that I have an interest in a rules-based solution, as evidenced by my participation in a discussion about differing interpretations of those rules. It is hard for me to fathom what possible evidence you could have that would suggest I am discussing the rules without having an interest in the topic. But again, as you don't want to discuss further, I'm left to my own understanding of my interest.