If you want open water you'll need a swim watch or the top tier forerunner watches (Fenix as well).
There isn't really any incentive for Garmin to offer this at the lower tier. They have devices capable for the sport, and expect you to pay the upgraded price.
It would be nice to have Garmin pay on the 245. I'm sure the device is capable with NFC, but if it's something I really want I know I'll have to go up a tier with forerunner, or forgoe the advanced running metrics and settle with a Vivoactive.
Personally, I've had to upgrade device models and tiers throughout my Garmin journey to meet my current needs. I'm well aware that a 945 or 955 (fingers crossed) will be my next device so I can have Garmin Pay, open water, advanced sleep... I would be grateful if Garmin brought those functions to mid tier, but do not expect it.
