they're marginally better since they have a platform-defined way to deliniate static from dynamic parts. ivi _can_ work without a runtime or build-time JS parser, while JSX cannot (because jsx has to be parsed out of full blobs of js)
on the dx/ide side, sure there's not a huge amount of difference if both had the same effort invested.
My feeling is that tagged templates would actually be a worse fit in this scenario because now you would have to distinguish between "regular" tagged templates and "templating" tag templates.
Personally, I don't think that it will have any significant impact, everyone will continue using React,Vue,Svelte and it is highly unlikely that they are going to adapt this new API.