Really, for me the negative change in CS over the years was the explosion in hosts who were sedentary. If you don't do shoestring travel as a lifestyle yourself, you won't be able to sympathize with your potential guest's needs. For a site that, in Europe, spread initially through the hitchhiking community, I was appalled to see so many CS hosts by 2008 who looked down on free travel, and threw around words like "freeloader".
I also can't agree with people complaining about guests who need their hosts to feed them. If they are ordinary backpackers who just budgeted poorly, that is one thing, but if they are intentionally trying to live on no money, that is another thing entirely. Among the freespirited alternative traveler community who founded CS, there have always been people traveling by providence, and they have been among my best and most memorable guests. Their stories and positive attitudes far outpaid the pasta and salad I made for them.
Finally, you can't assume that guests who write a non-copy/paste request actually read your profile. Sure, they may have quickly scanned your profile for things they can mention in a request, but that doesn't mean they care about the details. For years I could only offer a mattress on the floor and clearly said so in my profile, and yet so many of the guests who wrote ostensibly personalized requests either didn't catch that, or when they accepted my invitation and arrived at my home they complained about it. Again, writers of copy/paste are just as likely to be appreciative or not.
As for getting requests on BW or Trustroots, either live in a place where many travelers want to go to, or become a superhost whose house is open to all travelers and word of the good vibe there attracts people to your region even if initially they don't know what to do there. Those are your only options, really. However, this looks to be the biggest wave of CS refugees ever, so you may start getting more requests regardless.
And I have no problem with people that want to save money, but if that's the - only - thing they're using CS for, with no interest in ever talking to me, then I'm just not going to host them.
It's admirable to take in anyone, but it's pretty rare. The vast majority of hosts I know (and have surfed) will only take people in who have read their profiles.
Like I mentioned, there's a safety component to this (for men as well!) but also a practical side - many people live a good bit outside the city they're listed in, some people go to bed early or late, some people play music all night, some people are nudists, some people have a shorter sleeping spot (couch/bed/etc)... If you don't read profiles you're just rolling the dice - even if you just want a free bed!
By the way, I think I'll try to be more active on BW/Trustroots (hosting mostly.) Any advice for how to get my profile seen? On CS I get absolutely flooded with messages (and often get great, well written messages) - on BW and Trustroots I've gotten nothing.