As the petition calls for, it should be left to the teachers to decide. Even if the succes rate is 90%, are you happy to throw the remaining 10% under the reading bus ?
But so many teachers have been miseducated and they try to leave it out. Wyse and Bradbury at UCL are pushing non-evidence based approaches on the false authority of Margaret Meek Spencer [1] by making up a strawman of teaching only phonics, as if people that advocate teaching phonics claimed that were the only step in learning to read.
If that subgroup is 90+%, is it worth throwing the baby out with the bathwater? (I don't know the % here, I'm making one up as a thought experiment.)