Things like constant-time arithmetic are essential for safe and correct cryptography [1]. Treatments like the OP are accessible and can be helpful for beginner

Things like constant-time arithmetic are essential for safe and correct cryptography [1]. Treatments like the OP are accessible and can be helpful for beginners to understand RSA and public key crypto at a high level. However, the tradeoff is that critical details like side-channels are often neglected or not mentioned at all. [1] https://eprint.iacr.org/2021/1121.pdf https://eprint.iacr.org/2021/1121.pdf