When it comes to sourcing and recruiting, it's gotten easier to find people but it's gotten more difficult to get people to respond to emails, InMails, social messages and voicemails. The poor quality and lack of sophistication of most recruiter messaging, along with rampant spamming, certainly hasn't helped. Unfortunately and yet somewhat thankfully, the bar of what people expect to receive from recruiters has been set fairly low, so the opportunity for improvement is massive. The good news is that becoming more effective at getting people to respond to recruiting outreach efforts is relatively easy because marketing & advertising has already blazed the trail - sourcers and recruiters would do well to leverage what effective sales & marketing teams has been doing for decades.
In 2014 and 2015, I spoke at Talent 42, SOSUEU, and LinkedIn Talent Connect conferences on the challenges of getting people - especially "passive," highly recruited talent - to respond to recruiter outreach efforts. The decks I used for the presentations were mostly images, so I decided to add text to the slides so that the core concepts could be understood by anyone whether they attended those conference sessions or not simply by viewing the presentation (I wish more presenters would do this!).