Is it just a religious practice?

Circumcision is a surgical procedure that consists of removing the skin that covers the tip of the penis or glans, known as the foreskin. It is an ancient technique first performed by the Egyptians who believed it improved male hygiene. Nowadays, it is mostly a religious tradition among members of the Jewish and Muslim communities.
Regardless, circumcision can also be a purely medical procedure for some conditions in which the foreskin that covers the glands is unable to retract, or becomes inflammed, which are called phimosis, and posthitis, respectively. Recently, this surgery has gained popularity and may also be an elective procedure that is requested by parents or the patients themselves.
Arguably, the most discussed benefit of a circumcision is STI prevention. Both the CDC and WHO have even recognized this procedure as an effective public health measure. The thin foreskin, which creates a warm environment between its folds, facilitates the entry of pathogens. Therefore, circumcision has been shown to redice the risk of HIV and HPV infection by up to 60% and 30%, respectively. Importantly, the decrease in HPV contagions, translates into a lower risk for penis cancer.
Likewise, urinary tract infections, glans inflammation, and poor hygiene are also noticeably lower among circumcised patients.
With such important benefits, why are circumcisions still not widely implemented? As with any surgical procedure, there are risks. Although the frequency is as low as 0.2%, complications such as surgery-related infections, ulcers, bleeding fistulas, adhesions, and even glans amputations, may occur.
There is also a belief that circumcised patients have difficulties in their sexual practice. However, a study demonstrated that there is no difference in sexual function, achieving an orgasm, or erectile function when compared to uncircumcised patients.
The parents or the patient are the ones who can make the decision as to whether or not to have a circumcision. Most often, if not due to religious beliefs, the procedure is done in the hospital prior to discharge after birth. It can also be done with local anesthesia in the first 3 months of life. After this period, it usually requires general anesthesia.

References:

– https://www.uptodate.com/contents/circumcision-in-baby-boys-beyond-the-basics#H1

– Mehta KS, Marfatia YS, Jain AP, Shah DJ, Baxi DS. Male circumcision and Sexually transmitted Infections – An update. Indian J Sex Transm Dis AIDS. 2021;42(1):1-6. doi:10.4103/ijstd.ijstd_20_21

– Mehta KS, Marfatia YS, Jain AP, Shah DJ, Baxi DS. Male circumcision and Sexually transmitted Infections – An update. Indian J Sex Transm Dis AIDS. 2021 Jan-Jun;42(1):1-6. doi: 10.4103/ijstd.ijstd_20_21. Epub 2021 May 3. PMID: 34765930; PMCID: PMC8579597.

– Shabanzadeh DM, Düring S, Frimodt-Møller C. Male circumcision does not result in inferior perceived male sexual function – a systematic review. Dan Med J. 2016;63(7):A5245.