If you look to the actual summary conclusions, it doesn't say what you suggest.
Social transition conclusion: paraphrasing, "we're not sure."
Puberty blocker conclusion: "In summary, there seems to be a very narrow indication for the use of puberty blockers in birth-registered males as the start of a medical transition pathway in order to stop irreversible pubertal changes. Other indications remain unproven at this time." If you read science-ese, that's use it for the one thing, and then we're not sure one or the other on the rest.
Hormones conclusion: “There is a lack of high-quality research assessing the outcomes of hormone interventions in adolescents with gender dysphoria/incongruence, and few studies that undertake long-term follow up. No conclusions can be drawn about the effect on gender dysphoria, body satisfaction, psychosocial health, cognitive development, or fertility. Uncertainty remains about the outcomes for height/growth, cardiometabolic and bone health. There is suggestive evidence from mainly pre-post studies that hormone treatment may improve psychological health although robust research with long-term follow-up is needed”.
One of the failures of the report is it poorly organized, semi-political, and struggles to get to a point. They list a bunch of stakeholders and then express their opinions. That strikes me as political. "We listen." Except I am looking to you for objective conclusions from expertise, not a subjective Rashomon-style telling of the story from various perspectives.
Having mentioned in asides various digs at the therapies mentioned, bad faith folks like the poster here can then go pull out of the report where Cass mentioned their theory. Even if it's not the actual conclusion.
To me it's a big ol mess of a report which basically says "we don't know." If you are a conservative government running NHS, "we don't know" can be a useful excuse to cut off costly therapies at odds with your underlying morality/religion anyway. "NHS doesn't pay for "unproven.""
Except if you see the grander thrust of the report, it's that more study is needed, on every facet.