This will just force high SNR Posters to other platforms. ArXiv is rate limiting itself out of relevance.
The situation right now is pretty crazy, for example this established TCS professor [1] has at least 4 arXiv submissions co-authored by him in September [2]. This includes the recent breakthrough on the matroid secretary problem, which has a pretty interesting AI story of its own, if you haven't seen it yet [3].
Of course prolific professors can work around this by working with younger researchers who upload the work, but this just makes the rate limit a solo author bottleneck, which feels a bit weird.
[1]: https://en.wikipedia.org/wiki/Mohammad_Hajiaghayi
[2]: https://arxiv.org/search/cs?query=Hajiaghayi&searchtype=auth...
[3]: Concurrent Discovery Disclosure: The proof of the main result in this manuscript was obtained in a conversation with ChatGPT-6 Astra on Tuesday, September 15, 2026 at 1:02 AM PDT. We then prepared this manuscript for public release, with the intent of uploading it on the morning of Thursday, September 17, 2026. In the early morning hours of September 17, while finalizing the submission, we discovered the manuscript of Abdi, Banihashem, Hajiaghayi, and Mittal, uploaded on September 16, 2026, which contains the same result via an essentially identical approach. We are sharing our manuscript nonetheless in case our exposition is of independent utility to the community, and we hope this experience stimulates broader discussion about concurrent discovery in the AI era. (From https://arxiv.org/abs/2609.20797 .)
But yes, it'd be nice if arxiv also rate-limited co-author submissions with some higher number to discourage the most flagrant PI co-authorship abuses.
And in mathematics, at least, priority on results is determined by the first time it appears out in the wild; for most, this is the arXiv.
Nobody is going to accept waiting a month on something that they fear may be scooped, costing them years of work and thought.
This affectively makes the arXiv obsolete for much of the purpose it has heretofore been put to.
Whereas I would say "Have they put this on Arxiv yet?", mathematicians would say "Have they put this on the Arxiv yet?".