Almost all new cryptocurrencies follow developers, thus if you want to stay up to date on all new cryptocurrencies, you should follow developers on social media and Telegram. Also, if you are current and always active in the crypto exchanges Telegram channel, you will be able to know when new cryptocurrency is added.
It's not the cryptos that follow developers. do you mean to say crypto users follow the developers? you can follow the coin developer to check the updates of their creations but I think not all coin developers are active on social media because they have a busy life outside. There must be someone that controls their accounts, something like a fan page.
You should be careful and always verify if that was a legit person your following because anyone can now create a fake account and pretend to be someone else. Some crypto exchanges have a news feed and you can see their latest additions but on telegram channel? it's a known home for hype coins, be careful hunting coins on this platform.