I've also had a total thyroidectomy for thyroid cancer and my TSH is suppressed because I still have detectable cancer. So I hear you!! I had my first surgery 3.5 years ago and I still struggle hard with my energy levels. (I am a 43-year-old female.) I also did a round of RAI right after my first surgery that destroyed my gut. In the six months or so after the treatment, I developed intolerances to a whole list of foods, and because my gut wasn't functioning properly and absorbing nutrients, I became malnourished. I was a mess! I rarely had the energy to leave the bed/couch/house. Healing my gut even to this point has been a long, long road.
I've decided that there are two likely major reasons why I still struggle with my energy: 1) My gut is not yet flourishing. I know it's not as there are many signs. If my gut isn't healthy, then it's unreasonable to think it's doing all it should/could be doing to support all my systems. 2) I don't think my thyroid hormone replacement dosages are exactly right. I take both T4 and T3 (adding T3 changed my life by the way!), so one or both might need adjustment.
Since it doesn't make sense to adjust my meds and then heal my gut....just to have to adjust the meds again....I'm working on getting thriving gut health first. The more I read, the more I believe this is kind of the foundation of all my (our) health. In the last couple years, I'd gotten SO much better than I was that first year after my thyroidectomy so I'd gotten a bit complacent. I've actually even started working out! 5 days ago I was walking into town (which is only one mile) and I was soooooooo tired. I was just slogging myself down the sidewalk getting angrier and angrier that 3.5 years later this is still a thing for me. So, I've decided to get it handled.
I can't answer your weight loss specific questions, but it might be beneficial to see what's going on with your gut first and then focus on weight loss. Like the other people who posted said, you could have been eating foods that are compliant on W30, but still cause inflammation/SIBO in your body. Nuts are like that for me. My body hates them now, which makes me sad. Heal your gut!!
Also, I definitely agree with the recommendation for Mel Joulwan! When I found out I had to stop eating gluten, I hung up the phone with my nutritionist and cried. I didn't even like meat and nor did I know how to cook it. Well Fed 2 was the first paleo cookbook I bought and the first recipe I made was citrus sage turkey burgers (probably called something else). They were delicious! I had cooked meat that was delicious! And then I cried again. (I cried a lot there at the beginning.) She literally changed my whole experience and I love her.
So, I know your post is a few months old, but I just wanted to let you know you're not alone! Hugs!