Telegram's servers are far from "distributed worldwide": In fact, it currently has only 5 logical "data center"s, and while DC3 is still on, clues [0] seem to suggest DC3 doesn't actually carry user data at all now, and both DC2 and 4 are in Amsterdam, so essentially they just need to serve 3 locations.
Also, Telegram's protocol design only allows for connecting to user's home DC for any write interactions (except media, which in most cases still is home DC, or a "media DC" alongside the home DC). Bots are based on the same DC of the user, so almost all meaningful interactions will happen only on one DC for any specific bot.
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Telegram's servers are far from "distributed worldwide": In fact, it currently has only 5 logical "data center"s, and while DC3 is still on, clues [0] seem to suggest DC3 doesn't actually carry user data at all now, and both DC2 and 4 are in Amsterdam, so essentially they just need to serve 3 locations.
Also, Telegram's protocol design only allows for connecting to user's home DC for any write interactions (except media, which in most cases still is home DC, or a "media DC" alongside the home DC). Bots are based on the same DC of the user, so almost all meaningful interactions will happen only on one DC for any specific bot.
[0]: https://dev.moe/en/3025
And also all EU users have to remain in the EU