BIP Idea: incrementalrelayfee in feefilter?

The recent policy change regarding the feerate in Bitcoin Core has been implemented not only in its latest 30.0 release but also in the preceding 29.1 version. This update is significant as it reflects on Clark Moody's dashboard, showing that over 30% of listening nodes have adopted the lower incremental feerate, assuming default settings are used. This widespread adoption suggests a high probability, over 94%, that non-listening nodes connected to at least eight peers will encounter at least one peer supporting and rebroadcasting transactions with this new lower feerate.

Despite this progress in node policy, wallet adoption for creating transactions with reduced feerates or implementing replacements with the lower incremental relay fee appears sluggish. The slow uptake by wallets is attributed to the current unreliable state, suggesting that node policy changes outpace wallet support adjustments. This discrepancy highlights a lag in the ecosystem's overall adaptation to the new feerate policy.

A debate exists on whether special handling for the incrementalrelayfee is warranted. However, it is suggested that adopting a more general approach could offer greater benefits. In this context, the proposal of BIP 153: SENDTEMPLATE, as detailed in a pull request on GitHub, is presented as a potentially more impactful solution. This discussion points towards an ongoing evolution in Bitcoin's transaction policy framework, indicating a preference for broad, scalable solutions over specific temporary fixes.