I'm skeptical that developers talking to each other about how bad web bloat is will change anything. They will still face the same incentives in terms of ad revenue, costs of optimization, etc.
Here's a random idea that might have more potential: create an adblocker browser plugin that also colors URLs based on how slow they are expected to load, e.g., smoothly from blue to red. The scores could be centrally calculated for the top N URLs on the web (or perhaps, an estimate based on the top M domain names and other signals) and downloaded to the client (so no privacy issues). People will very quickly learn to associate red URLs with the feeling "ugh, this page is taking forever". So long as the metric was reasonably robust to gaming, websites would face a greater pressure to cut the bloat. And yet, it's still ultimately feedback determined by a user's revealed preferences, based on what they think is worth waiting how long for, rather than a developer's guess about what's reasonable.
Here's a random idea that might have more potential: create an adblocker browser plugin that also colors URLs based on how slow they are expected to load, e.g., smoothly from blue to red. The scores could be centrally calculated for the top N URLs on the web (or perhaps, an estimate based on the top M domain names and other signals) and downloaded to the client (so no privacy issues). People will very quickly learn to associate red URLs with the feeling "ugh, this page is taking forever". So long as the metric was reasonably robust to gaming, websites would face a greater pressure to cut the bloat. And yet, it's still ultimately feedback determined by a user's revealed preferences, based on what they think is worth waiting how long for, rather than a developer's guess about what's reasonable.