Feeling discouraged about my anxious dog

A year ago today, I adopted a dog from bad situation at 7 months old. He’s now 19 months old and while we’ve made progress, I still feel like he’s sort of set in his ways. I’ve spoken to a couple of experienced trainers and his vet about it, all saying that he’s still too young to start any anxiety medication and that trauma cannot be trained out of him. Basically, they told me that time has to pass for him to trust me and his surroundings. While he trusts me most of the time, he gets very growly and defensive when it comes to being touched in certain areas around his paws when trying to clip his nails and getting picked up when he doesn’t specifically indicate that he wants to be picked up. He lets me clean his ears but that’s about it. We recently moved away from our groomer that used to take him every time no problem and today tried out a new place and refused service as he growled at them indicating aggression. I asked his vet for a refill on trazodone as we had discovered that helps at vet visits and more anxiety provoking situations. I guess this is more of a vent than asking for advice but just wondering if anyone else has experienced a similar thing. Thank you.