"If I were very vocally against poverty and deprivation, and I read a lot of books and wrote papers and attended courses on poverty and deprivation, and contributed to blogs about poverty and deprivation, and became very angry with people who would blame poverty and deprivation on the sufferers, and maintained a very high profile socially as anti-poverty and desperation, I think if I didn't actually do anything material to help poor and deprived people, I wouldn't be surprised if others thought I was an armchair opinionist and possibly a tiny bit flaky."
I get your point, but I think you're undervaluing the work of talking about/publicising things. For example think of Joanna Lumley's gurkha campaign last year. What she did really was get the word out, then when she came to lobby MPs the whole country was behind her, and public pressure is what changes things.
Now look at this past month, the BBC has put on about 3 programmes about feminism (loosely) - and there is already a massive debate about it. People are talking about women's situations - not only in the UK but around the world - on this site, on the radio, in pubs. Maybe 5000 people might look at the LFN website as a result of that, if there is a campaign to write to your MP about a particular issue on that website, maybe 200 might do so. That's 200 letters that wouldn't have been written. The talking part of active feminism is not an end in itself - of course not. But you have to keep the idea that injustices are happening in people's minds, and then translate that into calls for action.
The "active" stage is then petitions, marches, protests, letter-writing campaigns to those in positions of power, sponsoring organisations that help women (if you can afford it - I currently can't), using your professional skills e.g. if you are a lawyer then doing pro bono work for female refugees from e.g. Congo.
Does that make sense?