Not asking a question, but sharing my thoughts about financial, bloggers boasting 1 mill or half a mill stock portfolio at the age of 30. Does it sound believable? ?

I think this is possible as I do see this kind of real life example. But most important is how we ourselves can learn from them and make ourselve better. I always take them as my role model as this able to keep motivate me moving forward.

Possible but I believe there's always a story behind how they got there. I would take it with a pinch of salt to inspire me in my investment journey but everyone's circumstances are different so do your best and enjoy the journey :)

Of course this is possible with media as multipliers.

however, whether to get very rich at a young age is a good thing? I am not convinced.

It's theoretically possible, but there's this saying:
"No evidence, no need for further debate."

Financial bloggers may have their own personal agendas, but I'm not here to speculate what are those agendas.

But if these financial bloggers are extremely hesitant in being transparent with their portfolios i.e. no screenshots of their portfolios provided on their blogs, or if they chose to be ultra-secretive and private about the contents of their portfolios, perhaps they're just cooking up a fairy tale to attract, retain, and increase readership for their blogs.

Availability of evidence, transparency, credibility, reputation: All of these go hand in hand in evaluating financial bloggers.