The impressive increase in market penetration of internet of things (IoT) services and the flourishing of targeted technology solutions forecast a prominent role for these applications in upcoming networks. For their success, the design of efficient grant-free based medium sharing policies is paramount, and represents a key challenge for beyond-5G systems. Motivated by this, the article reviews some recent results on the potential of receiver diversity, which is emerging as a very promising approach to boost performance of random access for machine-type communications.