For years, I carried a PLB (ACR ResQLink) rather than a Garmin because I believe it was better if I was in deep woods, under the canopy of trees, and had to call in the cavalry. Now, I still carry my PLB but added the Garmin Inreach Mini.
There is tremendous value to be able to contact emergency personnel regarding the nature of your problem. Maybe you need a specific type of treatment and alerting them in advance would save precious time. A venomous snakebite comes to mind.
If I were starting over, I'd get a Garmin InReach (Mini in my case) and pair it with my phone. If, and when, extra resources became available, I'd buy a PLB. I'm convinced they will better call in the cavalry if the heavens rain down fire and brimstone.
The Achilles Heal of the Garmin Inreach system is human nature. You forgot to charge the battery, or renew your subscription, or you changed credit cards and your subscription was not renewed using the old credit card!
A PLB is a set-it-and-forget-it device. Buy it, register it and you're to go for 5 years. Nothing to remember. As long you'll be committed to faithfully charging the Garmin InReach device and keep your subscription active, I'd suggest, without hesitation, getting it first. Here is an excellent analysis of the difference between a PLB and a Satellite messenger and, at the 29:30 mark, he talks which one to select and how to coordinate having both of them.