Niche question – sales vs lead generation

My expertise is helping coaches to double their conversions on their discovery calls. I enjoy helping them overcome the mind drama that stops them from being bold on their calls. I only want to work with people that are already booking calls and the last thing they need to figure out is the call itself and their mindset about sales. However I find that a lot of coaches struggle with lead generation but I don’t want to do that. I can help them with lead generation too but I don’t enjoy it.
Is it wise to not do lead generation and only focus on people who are already booking calls?