Forerunner 945 Series

Garmin Venu 1, 2, or even one of the newer Vivoactives would be great. You can get a Venu 2 for probably about $100-$130 on Facebook Marketplace right now. You can also get one of the older Garmin Forerunners for about the same price as well, if not a little cheaper

Use forerunner for swimming and it works great. So happy I no longer have to count my laps and I can just swim.

if he is working a lot in the rain, get him something with more than 2 buttons so he would be able to use the watch using only the buttons (without the touchsreen) if he needs to, something like a forerunner, or instinct (doesnt have a touch screen) or a fenix (but a fenix is one of the more expensive ones)

The same I was big on the Apple ecosystem and felt like it was a cool watch just because it integrated so well, but I never even downloaded any apps for it. All I ever used it for was timers and reminders and stuff like that and basic fitness tracking, and my forerunner does all the same stuffbut way better. Should’ve switched sooner

Dito. Venu will offer a tick “sexier” display due to oled, FR will most probably go longer. Might be a case for weekend hike ;)

All true except advanced metrics. They are also present in Fenix (it has even more features for hiking) and Instinct. Forerunner is not more advanced. The rugedness is mostly about the bezel. In fenix and instinct it has a rim which gives extra protection to the screen. But that means rugged watches are more bulky what can be a problem in the gym. The real question is lightness of forerunner vs battery life of fenix /instinct

You won't get "very accurate hr sensor" in any watch, they all use the same technology which has its own disadvantages. As long as I'm aware you can't program strength directly on any garmin watch.  Your best bet would be older fenix/epic/forerunner series 9