I have to say that I was quite dubious about phonics to begin with.
But the more I got to grips with it and used it to wach, the more I could see the benefits. On a basic level. When presented with the word "cat" for example, some children I teach, when prompted to sound it out, will say
"See ay tee" which doesn't help.
Some will say "cuh a tuh" which is slightly better and most will be able to get it. But ifthey just use the sound the letter makes when sounding it out, it often gives a much better idea of the word as a whole, so they'd get "c a t"
Obviously as they get older and are expected to read more words, phonics don't always help. But the children I teach are year 3 - 5 and we do a lot of recognising sounds and the sounds that patterns of letters can make, so for example we did an exercise where I gave them a vowel ad they had to pick words out of a list that had lots f different /a/ sounds like:
Paid make hay weigh etc
Then they had to list the letters that make the sound.
I don't know yet if its doing any good though.
But anyway, the point is, I do think phonics can be helpful, but I don't think it works for all the children all of the time