AGC will find its main application in surgical and inpatient uses, eg in cardiac, neuro, burn, ICU, and people with diabetes in any hospital setting.
Already banned:
No disagreement about AGC in the hospital -- there is a lot of lab/titration work in current clinical workflows for monitoring patient glucose levels.
Hat tip to you and sibling comment about continouous lactate sensors (seem like they are microneedle/patch based?). Quick review shows minimal clinical evidence, but maybe that's sufficient for the consumer wearable market.
They exist, a simple search will turn up a variety (how well they work is a different question). But see my sibling comment, they're banned from cycling competition.