it's not just Reddit. it's more websites every year.
I've worked as a sysadmin at companies who have done it. they blacklist an ASN which covers an entire ISP, or they just straight up ban the entire country. it's the easiest way to get rid of a few kids running penetration scans against the site or whatever. they don't get much revenue from the users in these countries and so they don't care. access to the collective knowledge of humanity is always getting smaller in developing countries.