No, federation works great in practice. I personally chose an instance I trusted to stay up and available, not one with any fancy domain or topic.

You can usually browse an instance without having an account, for example: https://mastodon.gamedev.place/explore (user directory) https://mastodon.gamedev.place/public (stream)

And once your instance federates with it (happens automatically, just needs any user to follow any user on the other one), you can search for hashtags.