The easy answer is: Do not worry, lots aren't meeting expected standards and are absolutely fine in the long run without anything extra happening. And that is perfectly true.
The harder question is: Is my child in the group that won't naturally catch up?
Which is the more important question, and one that can't be answered by people on here. it doesn't matter if 999 MNers say their child was fine if yours is the one that needed early intervention.
So, I think it would be perfectly reasonable to request a further meeting with your child's class teacher. Say that you are concerned that he seems not to be meeting expectations generally and you want to know how you can best support him to achieve.
You can't ask how many in the class aren't meeting expectations (and you may find that some of the grinning happy face comments are in that category, either because they're trying to hide it or because they didn't actually pick up what the teacher said). But you can ask whether the teacher thinks he will meet expectations by the end of the year.
They're not going to say sit him down and do 2 hours of cramming every night. What they might say is something like "he's struggling with blending phonics" which then you can see if there's an app he can play on your phone as a "treat" or when he's doing his reading you can pretend to get it wrong and get him to correct you.
Don't worry about doing too much, but you can just add things naturally to what you already do.
Cook together-he can weigh out or read the cooking time on packets.
Look for words he can help to read, maybe on the back of a cereal packet, or ask him to help you make your shopping list (if he doesn't like writing he can type it on your phone/computer).
Have a game when you're out-the number of letter "D" he can find.
Eye Spy games with sounds: So "I spy with my little eye something that begins with the sound F"
And when he says "phone" you praise him to the skies for being right and tell him how silly it is that it actually begins ph but sounds like f.
If he doesn't like writing, then (for my ds who was like that) a DSi using a stylus uses similar movements. Or chalk on the pavement etc.
Get his eyes tested. My cousin was very long sighted. Didn't discover it until year 1 as she was very good at hiding it-she would get her friends to tell her what things said and memorise it.
Equally well check his hearing. And just because he can hear the word "chocolate" at 50 yards doesn't stop him having hearing issues. (my ds had glue ear) Again they can mask it.
And if they do say they think there might be more to it than just needing time, then ask how they're going to help him. Because it may be that he does need extra help. That doesn't mean he always will, but early intervention can make a huge difference.
You're looking to support your ds in the best way you can. Your teacher wants to do that too.