I do get the concern about the EA forum being very serious. I myself find it intimidating to write here and very much share the sentiment of Olivia Addy's great post. 

At the same time, I don't think the culture here should change.

In defense of gatekeeping:

1. There are already EA communities that are more casual - on Reddit, Twitter, Facebook and Slack. The forum presents a unique niche.
2. I assume most people lurking the forum are more on the casual side (pulling it from general internet user base rates?). I'd worry that less-serious posts would get more engagement for the virtue of being less-serious and more accessible to people new to EA, while more sophisticated posts would be drowned out.
3. I'm not sure if you can stop the culture shift when it starts (see: Thresholding - by Duncan Sabien - Homo Sabiens). And when it changes enough, the people who were initially the most engaged stop posting. 
    

Anecdotal examples from my n=1:

• A Discord server for negative utilitarians - I once went through all messages spanning a few years (don't ask me why) and saw the shift from a discussion not too different from the EA forum, through gradual casualization to the current state where it's mostly young people discussing suicide and venting about their arguments with 'breeders'. The people who engaged with the server in the beginning, when it was EAforum-like, have completely stopped posting.
• Another Discord server I was in went through the same shift - some people joined the server and gradually shifted the culture towards something resembling Twitter. They weren't doing anything bad enough to be banned (thresholding problem again), but dominated the discussion and made the veterans leave. In the end, the server got closed by the admin, citing the culture shift.
• Exactly the same happened to a fairly large Facebook group I was in. It got closed down as well.
• I observed that as subreddits grow, the culture undergoes the same shift. It takes a few people to start posting less thought-through content -> the silent majority of casual lurkers upvotes these posts into the frontpage -> people see that and start posting more of this kind of content -> veterans leave, because it's not the same space anymore.

It may look this way, but I have nothing against casual communities. In fact, in the majority of communities I'm in I am the casual lurker upvoting the memes and skipping over dissertations. I think both kinds of spaces are needed, it's just that the more niche ones need some curation/protection.

Maybe putting a link to the EA Anywhere Slack somewhere visible would be a good idea? I only learned about its existence at the recent EAG, and I think it's the kind of space that a lot of people here are after.

During the EA forum voting week I did some research into the orgs that were listed and I was impressed by RP's detailed doc on what they'd use the funding for; I hadn't been aware of the work you're doing in the field of animal welfare. I care for invertebrate welfare as both the scale and neglectedness of the problem are enormous, so the projects listed got me excited.
Keep up the great work!

This year I started montlhly donations to ACE recommended charities fund and Anima International + made some individual donations to THL, Hive and others. I'll be switching to Rethink Priorities in the new year.

I think offsetting your emissions and offsetting your meat consumption are treated differently by EAs because they really are different.

I liked the two examples presented by William MacAskill in 'Doing good better':

1. Offsetting your contribution to climate change by donating to CoolEarth, so that all the CO2 you produce gets offset before it gets to harm anyone - the 'undoing harm' kind
2. Donating to an org that advocates for not cheating on your spouse to offset your cheating on your spouse - the 'apology' kind

In the second case the damage is already done; by offsetting, you just prevent further harm. Eating meat while donating to animal welfare organizations is more like the second example. You harm some animals and then pay for some other animals to be saved. You can't undo the harm done to the animals harmed.

I may be mistaken, but I think the author was referring to positive beliefs (as opposed to normative beliefs), in which case your points 1 and 2 would be addressed. It's not made clear in this article but that's what I believe based on the context I first read this essay in (a series of blog posts collected in the book "Map and Territory"), which was more about seeking truth than doing good.

There seems to be a mistake, the link at the beginning leads to the nuclear weapons problem profile.

After some reading I moved my votes around slightly as I can't rationally justify not giving more weight to potential invertebrate suffering + these causes likely won't attract too many philanthropists from outside EA.