From what I can tell, et al. is not about socio-political power*. It's just a necessity for ease and efficiency. In-text citations need to be short to limit wasted space. Otherwise, we'd have lots of text dedicated to unnecessary names. An in-text citation that reads (Perez et al., 2023) is much more efficient than (Perez, Washington, Smith, Iwukuni, Johnson, Patel, Boofy, Yamirez, Tate, Hendrix, Apple, Man, & Gargamel, 2023).
Using 7th ed. APA, the citation entries in the bibliography/references include upto the first 20 authors, so contributors are rarely omitted.
Perhaps being the first author is in many situations, but APA format can't really address that.
It's not like these are written on literal paper. It's the 21st century, There's no reason to save space in digital documents when you can just format them differently.
Screens still have real estate that you need to fit onto. You can do "click to expand" but frankly, who would look at that. You could have the full list in the bibliography section, but frankly, who reads all that: The stuff I look at is the citation abbreviation ([Miller et al 2003]), then the doi or journal/paper title to copy and paste. Everything in between gets ignored, if I read names then it's on paper titles, not citations. I've also seen a tongue-in-cheek proposal to overlay all author names on top of another in citations, sadly can't find the paper.
Typography isn't the place where you want to attack this issue, at most you can get some token feel-good result that will be ineffective because it ignores the psychology of people looking up papers. Which is to say: You'll do net damage to your cause because you're spending goodwill capital on feel-good BS. If you want to have a systemic impact then attack the issue from the other end, such as cracking down on people which insert themselves as first author of every paper coming out of their department and stuff. Rule of thumb: If someone can't do a thesis style oral defence of a paper, their name has no business being anywhere even close to the front. I don't care when the administrative boss is listed at the end, though they should have the decency to put themselves after any assistant who did actual scientific work, even if it's just pipette wrangling.
Equality of et al - how about no one gets their names inserted into the paper, everyone is just put in the bibliography. No "first authors." Instead, the institution gets the reference i.e. instead of (Miller et al 2005) it can be (Cornell U. et al 2005). Then, because it's digital, mouse over the reference for a full list of people involved.
Solves the problem of worthless administration slapping their personal name on it.
The IEEE reference style guide actually often works just like this, the entire reference is just a number in brackets in the text and then the details of the reference is in the bibliography at the end. For example
...a high correlation as shown in [5]...
[5] A.N. Author, P. Ostdoc, and O. Verworked "A paper about a thing" Department, University, City, etc.