#tldr: fact check is partly true. op's numbers are missing some context but they're absolutely correct in pointing out that

[frogeyedape]

Fact check: where the fuck did these numbers come from. See

Overall, 25 099 patients (52.3%) were aged 19 to 30 years, 10 476 (21.8%) were aged 31 to 40, and 3678 (7.7%) were aged 12 to 18 years. When stratified by the type of procedure performed, breast and chest procedures made up a greater percentage of the surgical interventions in younger patients, while genital surgical procedures were greater in older patients.

3215 patients (87.4%) aged 12 to 18 years underwent GAS and had breast or chest procedures

405 patients (11.0%) aged 12 to 18 years underwent genital surgery.

Above quotes are for data collected for 2016-2020.

The followup study (which i believe op references) addresses the gap in cisgender affirming care vs trans & gender diverse (TGD) affirming care:

Gender-affirming health care aims to align an individual’s physical gender expression with their intrinsic gender identity. An example is breast reduction for cisgender males with gynecomastia. Recently, there have been increased legislative efforts restricting gender-affirming health care specifically for transgender and gender diverse (TGD) people.1 Proponents of these efforts express concerns that TGD minors may be too commonly using gender-affirming surgical procedures. Given stringent clinical standards for gender-affirming care,2,3 use of gender-affirming surgical procedures by TGD minors is expected to be low. However, there are limited national data; while 1 study provided national estimates, it did not capture minors under the age of 12 years and did not exclude procedures with clinical justifications outside of gender affirmation.4 Therefore, using a national dataset, we evaluated the extent to which TGD minors and adults received gender-affirming surgical procedures in 2019. Additionally, in line with a recent publication from bioethicists to acknowledge that gender-affirming care is used by people of all genders,5 we provide a novel characterization of the relative use of 1 gender-affirming surgery—breast reductions—by TGD and cisgender populations.

Note the following quote is for a single year in the US, 2019.

The rate of undergoing a gender-affirming surgery with a TGD-related diagnosis was 5.3 per 100 000 total adults compared with 2.1 per 100 000 minors aged 15 to 17 years, 0.1 per 100 000 minors aged 13 to 14 years, and 0 procedures among minors aged 12 years or younger (Figure 1). Of gender-affirming surgical procedures identified among adults and minors, 1591 of 2664 (59.7%) and 82 of 85 (96.4%) were chest-related procedures, respectively. Of the 636 breast reductions among cisgender male and TGD adults, 507 (80%) were performed on cisgender males. Of the 151 breast reductions among cisgender male minors and TGD minors, 146 (97%) were performed on cisgender male minors (Figure 2).

Fact check: there were 151 breast reductions in (insured) minors in the US in 2019, of which 146 (97%) were for cisgender male people. Among minors, the only surgeries identified as for gender affirming care specifically, 82 of 85 (96.4%) were chest-related procedures.

Furthermore (and supporting op's point):

In this cross-sectional study of a national insured population in 2019, there were no gender-affirming procedures conducted on TGD minors aged 12 years and younger, and procedures on TGD minors older than 12 were rare and almost entirely chest-related procedures. Additionally, when considering breast reductions among cisgender males and TGD people—a surgery that can be considered gender-affirming among both populations—most were performed on cisgender males. Thus, these findings suggest that concerns around high rates of gender-affirming surgery use, specifically among TGD minors, may be unwarranted. Low use by TGD people likely reflects adherence to stringent standards of gender-affirming care.2,3

When you look up gender affirming surgery it says 'a broad range of procedures that help transgender and non-binary people transition to their gender identity'.

Seems 97% had the same procedure.