There is exactly one time where the series has brought up sexual orientation so far:
https://dynasty-scans.com/chapters/whispering_you_a_love_song_ch28#23
I do agree that ignoring it almost-entirely-but-not-quite feels a little off. There's this one time Yori thinks about it when it comes off as silly considering every single relationship involving the people close to her including herself is homosexual, and there's Miki being the token straight character which I found funny earlier on in the series, but now that she's been brought into the fray of all the lesbian relationships herself it feels like that detail of her character is something the author didn't really think through and is being carried over just to avoid contradicting it.
I once read a definition of yuri as "lesbian themes without lesbian identity," and I feel like that's very apt for a lot of yuri works, particularly "fluffier" ones. It's a little less common these days, but it's still around.
There are Yuri manga that do go into lesbian identity, though there are a good amount of straight forward romance stories, along with escapism. Which can be fine in theory? There's room for both hard hitting series that delve into identity, the complications of it, the difficult feelings, and for series that are just to the point romance that focus on two characters being in love and that's the point. I don't think it's good to simply dismiss any and all fluffier romance as not real lesbian media, or gay media as well for Yaoi, so fourth. Maybe that's a controversial opinion though.
There's a manga that goes into lesbian identity that I love, the author celebrates pride and pushes for IRL acceptance in Japan, and the message I really appreciate from the series/author is that a person should enjoy whatever LGBTQ media they want and what matters at the end of the day is pushing for acceptance in real life. Not just accepting LGBTQ in stories, but also in real life, that's what actually matters. You can enjoy Yuri/WLW/GL, live action lesbian movies, gay movies, fluffy, serious, tragic, anything and that's fine. Just make sure you're also involved with achieving and celebrating better rights and acceptance in real life for real people as well.