Bluntly: No list on this article will include all actors involved with portraying the character or all the forms he has take. Using that lack of inclusion to insist on a poorly structured, not overly informative trivia list, does not make a lick of sense.
As stated by the Admin when that list was removed from the "Aliases" section of the infobox, it's overkill.
Frankly, the list should be limited to principle cast for a given season. Meaning "Rand O'Reilly" shouldn't be there as the actor only worked on the one episode. And then there are the cases of Chyler Leigh, which is straight forward, and Erica Durance, which isn't.
I'm doing my best to be civil here. I have relocated the information on aliases to the notes section to hopefully appease all parties.
Also, you do not have the authority to bluntly tell me what I can and can not do; that is for the admins to message me about. I have not posted false information. I have not vandalised the page with proganada for a political agenda. And I have not removed anything that counts as information. If this is bothering you so much, by all means contact one of the admins and we can discuss this with someone who does have authority.
Just please stop undue my valid edits on aliases for the Martian Manhunter without further explanation aside from that you don't like it.
About you "valid" edits. Yes, part of them are. Pare of them are not.
J'onn J'onzz/Hank Henshaw is portrayed by David Harewood.
J'onn J'onzz is portrayed by David Harewood in both his Martian form, under heavy prosthetics, and in his guise of Hank Henshaw.
The first is consistent with other articles on live action characters. A compromise has been place into the article.
When J'onn takes on the appearance of others, different actors take on the role, such as Melissa Benoist when he steps in for Supergirl, as in the episode "Blood Bonds", among others. Others actors have included, but have not been limited to:
When needing to use another form to his advantage, such as to remain undetected and catch an opponent unaware, J'onn has been played by Cole Michaels, Ava Wilson, and Peter Prontzos.
The expansion/explanation of why is unneeded in this context as the section id from a real world perspective. The simple fact that the character can shape shift, and that he is then portrayed by other actors is sufficient.
Leading with the initial regular cast member as the primary example is preferable to what amount to credited extras.
Cole Michaels, Ava Wilson, and Peter Prontzos are not going to get "Actors:" articles based on the IMDb pages for the three. And there is nothing to link to at Wikipedia. Listing them is extraneous fluff.
Identifying and episode as an episode is a good thing as it clarifies what is being referenced.
Listing multiple episode of where thecharacter took on the appearance of another specific character is either over kill or over indulgent. the end of the original scentence ", among others." is sufficient to point to Benoist portraying a disguised Martion Manhunter for more than the single episode.
"Others actors have included, but have not been limited to:" is consistent with the intent of this bullet point. It also makes clear that the following list is not exhaustive.
As for that list:
the "Actor/Role" should clearly state that it is disguise. neither of our formatting really did that. I've updated it for that clarity.
See above regarding identifying an episode as an episode.
Going beyond the regular cast to include one-off characters, even if the character is named and is plot specific for the episode, is unnecessary padding.
Jason Gray-Stanford may warrant an article, though that is unlikely. Rand O'Reilly only exists in the continuity of Supergirl, there is no counterpart for him in the comics. And this is Gray-Stanford's only appearance in something adapted from a DC property to date.
Gregg Henry, based on IMDb, is likely to get an article at some point. That does not justify padding the list with him.
"Noel Neill" fits the criteria for reasonable inclusion since Erica Durance was a member of the cast with a recurring role for that season. But that inclusion needs a better explanation than you bothered to give.
All I'm seeing is a bunch of technical terms that have no meaning to me. So I've removed the list entirely and returned the page to how it was. If this can only cause conflict, then the best way to avoid conflict is to remove the motivation entirely