SarahInAccounts - Not necessarily. The forum I run has a facility for seeing what was there before the edit.
It is no help "seeing what was there before the edit" when "the edit" can occur at any point after people have replied. I mostly visit FWR and threads can be very fast moving. Dozens of replies could be posted before a post is edited. At the moment, if a genuine correction is needed it is usually the post immediately afterwards and the situation is completely transparent.
DGRossetti - "Hundreds of other forums manage without too many complaints."
You visit "hundreds of forums" and know this for a fact? I have been moderating all manner of "special interest/hobby", professional and political Forums and Facebook Groups for 20 years.
Free editing of posts by users is usually helpful and not abused because most users are decent people who do not set out to cause problems. However . . . it is the easiest way for a troll or troublemaker to wind everyone up and cause a huge problem and that is exactly what happens.
Other times someone can think better of an angry/insulting/red-mist post, edits it after others have responded and it leaves a whole host of people looking like jerks for apparently responding intemperately to what seems to be a reasonable post. Even when edits are visible, or can be revealed as on Facebook, the damage is done.
This sort of thing can leave a very bad taste and destroy the atmosphere of trust that makes a forum a "community" rather than a bunch of random strangers.
Facebook Groups are a nightmare to moderate when there are complaints and people edit posts. You might have to trawl through repeated edits looking at time-stamps to work out if a complaint is justified. The outcome might be that someone is permanently banned so it has to be done.
Things might look fine on the surface of Forums that you visit but behind the scenes there might be Mods losing the will to live while they mediate between members and try to sort out "who said what, when".
I post almost exclusively on the FWR Board on Mumsnet, which is already bedevilled by trolls and "goady fuckers". It is also heavily "monitored" by non-members who screenshot content and share it on other platforms, as well as reporting posts and threads after the trolls and GF's have wound people up - or have used sock accounts to insert offensive content.
I am 100% certain that these people would abuse an unlimited Edit function! The cost of a Premium Membership would be unlikely to deter them as it is obvious from the content posted by some of these accounts that they are shared between people who team-up to cause problems for Mumsnet members posting on FWR.
Please believe me, just because you are unaware of problems on other forums you visit it does not mean that there are no problems. They might not be targeted by trouble-makers in the same way as some Mumsnet Boards.
ps. FWIW I will pay up to keep Mumsnet afloat. I am not wealthy but my expenses are reduced due to Covid-19. This is something that is "non-essential" but that I would prioritise.
Moderation of FWR, in particular responding to unreasonable complaints from non-members , can be infuriating and I would second everyone who has complained in previous posts.
I would add that the banning of certain terms, like "TiM", because they "offend some trans people" sticks in my craw. In doing so, Mumsnet is favouring a sub-set of trans people. It is notable that trans people who post in good faith on FWR usually state that they are not offended by such terms.
However, Mumsnet offers what few (any?) other sites offer in that Politicians are willing to engage directly with members (there is a record of Parliamentary achievements on the site somewhere); it is on the open internet rather than behind a pay-wall and so provides an invaluable resource and support for so many women - who do not even need to register in order to benefit.
I would much rather see Mumsnet survive than fold for lack of cash. It is not perfect - but what is?
Could it be improved? Yes - but members will never all agree on everything that would be an improvement.
The Edit Button might come - and I hope I am proved wrong about the trouble that I think it will cause.
One thing that almost all of us who are anonymous on FWR are rightly concerned about is the ability to remain anonymous and not be doxxed. I am going to risk subscribing but I really wish it was not a risk.
There are plenty of people here explaining that the risk is too big for them to take in view of the real life consequences that could follow, like losing their jobs due a false accusation of "hate speech" being logged with the Police - and no right of appeal. Or women being tracked down by abusive ex-partners or stalkers.
This above all else needs to be taken much more seriously by Mumsnet - the safety of members. Not just "Premium Members" - all registered members.