I'm not sure if it ever was that hard but if you follow a bunch of people the network effects will kick in eventually, you can also add relays to pull in posts from other servers if you're impatient. A fresh instance can take some time before the known network starts filling in, especially if you don't know who to follow (or have anyone following you), but fedi is a series of tubes: it only pushes and pulls stuff from places it knows. I didn't have problems federating outgoing messages to my friends' instances when I started, but I wouldn't be surprised if some Mastodon servers use some stupid anti-spam measure that keeps low peer count servers away.