Like you, I much prefer email or online communication to a phone. It's just much less intrusive for both parties. If, however, an inquirer requests a phone call, I call them, especially now that HA/VRBO recommends a phone call to guests prior to booking. I'll communicate with a potential guest however they prefer.
I do advertise on multiple sites, some work better than others, but a lot of that may depend on your area. I've read posts from someone who get more results from listing site A and notthing from listing site B, while someone else is the exact opposite. Some sites work better for some folks than others. Why? Location? Maybe. Who knows. Try some, keep what works and throw out what doesn't.