@rysiek There's going to be a Birds of Feather session on Saturday about organising sponsor-free conferences, which deserves to get some attention as it's obviously very relevant:

At NixCon 2024, we took the bold step of going completely sponsor-free—and it turned out to be a great success, with 400 attendees, making it the largest NixCon to date.

In this BOF session, I’ll share my experiences as a core organizer, including the challenges, lessons learned, and tips for anyone looking to organize their own sponsor-free events without breaking the bank.

https://fosdem.org/2025/schedule/event/fosdem-2025-6721-organizing-sponsor-free-conferences-bof/