There are many issues from an eSIM adoption standpoint, one of the greatest barriers to adoption are actually the SIM vendors themselves. Unlike the silicon valley giants that have mastered technology and changed our lives at scale, the SIM industry is dominated by four companies that comprise about 80% market share (Thales, Idemia, G+D Mobile Security and Valid). For 30 years these companies have been pumping out SIM cards from factories around the world, and to flip to a fully digital paradigm requires a complete change in mindset and operational orientation. The introduction of the eSIM puts these companies squarely into the real time provisioning path forcing them to operate more like Amazon Web Services and less like a process driven factory. But as history as demonstrated, many companies have failed to successfully transition. Just think of Kodak and Blockbuster Video just to name two.
Because of this, wireless carriers have not had a high degree of confidence in the SIM vendors resulting in relatively low eSIM adoption. But rather than proactively investing and building out highly scalable eSIM infrastructure, the SIM vendors took the approach to price gouge the carriers. In the SIM card days, carriers ordered SIM cards, received them and paid, but now SIM vendors have begun charging for hosting eSIM platforms and their setup fees, they charge to develop eSIM templates (called profiles), they charge to create an eSIM and they charge to download them. And on top of that, they provide lackluster support at best. So with multiple costs that carriers must pay, it should come as no surprise that adoption has been low, even though eSIM technology has been around for over 10 years now.
As handset OEMs embark on their eSIM-only roadmaps, the single greatest risk is that the SIM vendors do not perform well resulting in failed activations and/or fumbled eSIM downloads. The only way to mitigate this is for the wireless carriers to take full control of their eSIM ecosystem, as after all, who is better at operating wireless networks than the wireless operators themselves.