If you want your Chrome to be as fast as possible, you would get rid of all extensions you have. It doesn't matter even if it's an adblock atp.
Hence calling it a feature, not a bug is rather misleading. Since you went and installed plugins understanding that it might and it will affect your workflow.
Pre-manifest V3, when OnBeforeRequest actually blocked requests before they were downloaded, browsing typical sites with it enabled was objectively faster than with it off. Any overhead was pretty quickly recovered in not downloading the ads.
Hence calling it a feature, not a bug is rather misleading. Since you went and installed plugins understanding that it might and it will affect your workflow.