Well it a nuanced issue. Everyone has mental health and physical health and it can range from good to worsening (especially with life stress, so I think its postive overall that people are willing to discuss normal human emotions more), without being an illness or condition. You can talk about being sad but not equating that to clincal depression. But we have this for physical health as well, people complain about colds, random joint pain, stomach pain; it doesn't mean they're pathologizing themselves with physcial illness.
So I think we instinctively react different when it's mental health because sometimes even unconsciously it's still taboo. Only 8% is spent on mental health v physical health in the NHS front 9% a couple years ago despite 1 in 4 people experiencing a mental health condition annually according to Mind (temporary for some or life long for others). But even those who struggle temporarily need to manage their symptoms more and be aware if they relapse or need more support.
Many more people are struggling (especially wiyh longer wait lists) and are often not properly treated just made 'safe' because on the NHS normally you only have access to CBT for 6 sessions or maybe with diagnosis 15-20, which is often not enough to get to the bottom of issues, and many cannot afford private therapy and often people can't access different therapeutic methods easily (EMSR, IFT, somatic, etc) as less people are qualified (as its often not mandatory to get the job, but the NHS is expanding this slowly).
Also people can feel they can't talk about when they're struggling sometimes so like to drop hints, because there is still plenty of stigma. Obviously not everywhere and there is a problem with health misinformation (just think about how people now are drinking raw milk or saying we shouldn't have fluoride in toothpaste). But also the increase in discussion about mental health and other condition e.g ADHD in girls which initially was never researched in studies because they thought girls didn't have it and now we know they often present differently has helped many get diagnosis. When they were struggling their whole lives but didn't get the right support.