The point of the heter, in my opinion, was to not keep the husband chained forever due to unfortunate extenuating circumstances. As with anything in life that was created with good intent- there are those out there that will exploit it for horrible purposes which goes 100% against what the creators had in mind. The Heter Meah Rabonim is no exception.
You make a good point regarding the current state of Batei Dinim nowadays. If things worked a little better, even in the fragmented state of our communities, if a person is summoned to a Bais Din that he’s not familiar with he should be able to call a local Bais Din to see if they are legit or not (kind of like a hashgacha that he’s unfamiliar with). If research does show that it’s unfortunately a corrupt Bais Din, the litigants (who are hopefully only out for the truth and for what Hashem wants them to do) should be able to find a Bais Din that works for both of them.
When I got summoned to a Bais Din I never heard of a number of years ago I reached out to a dayan on a Bais Din that I was familiar with and trusted. He informed me that the particular Bais Din was as corrupt as they get (one of the dayanim was later arrested and is actually sitting in jail at the moment). Under the guidance of Daas Torah, I informed the plaintiff that I was not going to answer the summons but he is welcome to work with me on choosing a Bais Din that we both trust. He refused to even try that. This showed me that he wasn’t trying to get the emes (to say the least).
Thanks for the link you tried posting- it looks like I was mostly correct with what I wrote earlier with the exception of the dates.