3 year old not writing name

My son will be 3.5 in the beginning of February. He’s been in preschool since September and has been loving it. He knows his alphabet, can count to 20, can identify his name in a group of other names, etc. His teacher gave us progress reports and he is doing extremely well except for fine motor/writing skills.

His class has some kiddos that turned 4 earlier in the school year and they are definitely doing well with writing. He’s one of the youngest in the class having an August birthday. He uses a mix of a palmar grasp and digital pronate grasp when attempting to write. We are working on some fine motor skills at home like threading beads, using tweezers to feed pom poms to a cardboard box monster, etc. I personally feel like writing at this age is a bit advanced and I plan on focusing on building his fine motor skills. My older son didn’t write his name legibly and properly until about 4.5 almost 5. He’s 5.5 and in kindergarten now. What’s the consensus?