An alternative search for trash pump:
https://www.ebay.com/sch/i.html?_from=R40&_nkw=trash+pump&_sacat=184085&rt=nc&Power%2520Source=Elect...
Many sellers are listing flow rates in gallons per minute; I noticed several 53 g/m units.
I understand you are pointing out difficulties with the search that some buyers will encounter. Like you, many of those buyers will try an alternative search and wind up finding what they are looking for via different means.
Could eBay change things to make it easier for some? Of course.
Would a particular change make some other things harder for other users? Maybe.
Might eBay be taking both of those into consideration when deciding whether or not to implement a change? Difficult to say with any certainty, but eBay likely has better data than you or I, and eBay has an incentive to get it right or lose lots of money.
That is not to say that eBay always makes the right choice, or that those choices are implemented correctly; clearly some things are broken, such as the "Lowest first" sorts where 99+% of the results are filtered out entirely.
But it is also clear eBay thinks "Lowest first" sorts should be doing some filtering, despite what many people assume about how sort is supposed to work; otherwise eBay would not have implemented the "see more results" message. Users still need to convince eBay that the filtering is going too far, and the "see more results" message is not always appearing as it should.
Often it is not enough to simply point out that things are "broken". You may need to demonstrate to eBay that "fixing" things is actually worth it. And in many cases, someone at eBay may still be convinced that things are actually working as intended, even when they are clearly not.
