I can from a number of other Fediverse platforms. I may not be able to follow you on Lemmy like I can follow a community, but I can still find your account to see your posts and comments, and that limitation doesn't really impact me having to have per-instance accounts versus having a fediverse-wide account. I have probably a dozen fediverse accounts across multiple platforms. I want to have my fediverse identity able to access all fediverse platforms and that other people using that platform can find me as.