In "Rejoined" everyone was freaking out at the idea of Lenara and Jadzia even being on the station at the same time. Lenara's brother watches them like a hawk. Sisko offers for Jadzia to take a leave of absense. Fast forward to Ezri's arrival and no one bats an eye about her being around all these people from her past life on a daily basis, including her husband.
The problem isn't with Jadzia and Lenara but with Dax and Kahn. The difference is that Dax and Kahn could sustain a romance across centuries
, which the rest of Trill society wants to avoid. Dax wasn't going to keep working at DS9 for centuries, so Ezri's return wasn't a problem for Trill society and it wasn't going to stunt Dax's experience.