The Arrowverse formula's handling of secret IDs is getting pretty ridiculous, at least judging by The Flash, which I just stopped watching partway into this season. (I'm just tuning in for the crossover event at this point.) It's a bit much when anyone who dates a member of the team is entitled to know Barry's secret.
I sometimes wonder if the change from older superhero shows where nobody but one or two people knew the hero's identity to newer ones where almost everyone knows is a reflection of the age of cell phones and the Internet. Everyone is connected to social networks now, so we know more about each other and have fewer secrets, and that reflects how we approach the stories we tell.
Although of course it's partly due to modern serialized storytelling. That demands changes in the status quo and developments in core relationships, and having friends/family discover a hero's identity provides such a development while also enabling further developments as the supporting character is brought more directly into the hero's core storylines.
Anyway, it's because of that last bit that I don't mind the modern practice. It's often harder to do much with a character who doesn't know the hero's identity. Often a character doesn't really come into their own until they do discover the truth and become more central to the storylines. Iris West was a wasted character in season 1 of
The Flash, but once she was in on the secret, she became far more integral. And personally I think
Spider-Man's Aunt May was never a better character than during the period in the early 2000s that she learned Peter Parker's secret identity and became an invaluable confidante and supporter of his superheroic efforts.
Granted, I'm not sure
Supergirl's Lena Luthor is a better character for being in on the secret now; if anything, she's kind of become less interesting than before. Though that's largely because of how long they kept her in the dark, so that when she finally found out, she felt betrayed and embittered.
Really, that's another reason I don't like the secret-identity trope. Constantly lying to your best friends, family, romantic partner, etc. is a jerky thing to do. And the excuse for it is lame -- "I hide the truth from you so my enemies won't target you." What difference does that make? Superheroes' best friends constantly get attacked/kidnapped by bad guys anyway. If a bad guy just
thought they might know the secret, they'd still get tortured whether they knew or not. Keeping the secret is only about the heroes protecting themselves, not their loved ones. If their loved ones knew they were connected to a superhero, that would make them more aware of potential danger and better able to protect themselves. So it's a hypocritical trope. Keeping your identity secret from the general public is one thing, but the people close to you deserve to know.