I too just replaced the OEM battery in my 2012 Fit.
It is over 7 years old and the car has 127000 miles. (I am on original front brake pads too, btw).

The original battery was also a Yuasa from Japan and the Honda's new OEM is built in Mexico.

I did add distilled water to the OEM battery about a year ago (the sticker comes off and the cell caps become visible).

The symptom of the originally battery going bad was also a sluggish cranking, especially after the car sat for a day or so.
The voltage after driving it was only 12.4 volts, indicating low state of charge.

Took it to Autozone to do a load test and the tested showed "bad batter" result. (it must have dropped below 9 volts while loaded for 15 second, the nature of load testing).

With new battery, the car cranks instantly as before.
Only time will show how good the Mexico made Honda batteries are.

 

both my digital obd guage and dashcam is connected to the obd and notice battery drain so decided to use an obd splitter with turn off switch so i switch off the connection before i leave the car

 

I just experienced a dead battery (4 year old battery) and I was just sitting listening to the radio with the car off and I also have a cheapo bluetooth dongle. I think you're onto something here.

 

Mine lasted 2 years but I’m in Texas, super hot in the summer and very cold in the winter, and I have a remote start system installed so I expected the battery to die early. I had AAA replace it (I want to say that I read somewhere that they use interstate batteries?) and laughed when I saw how small it was. I didn’t know that batteries for passenger vehicles could be that small. My MINI had a normal sized battery, as did my Buick Encore, so the size of the Fit’s battery was a surprise.

 

You can fit a larger battery. The space is there.,,,,and the larger they are, the more storage capacity. ......Am currently running size 26R....

 

The OBD2 port is always powered and there's no switched 12v so the dongle is always on. It shouldn't be a problem for a good battery under regular driving, but mine was pretty worn and when I left the dongle plugged in, the battery was flat within a week of not driving the car.

Around 4-5 years is what I often hear but can be more or less depending on conditions. The Varta in my Miata lasted way more and that's including running it flat several times, oops.

 

Update: AAA replaced the battery (under warranty) at 15 months. I’m going to get the larger battery next time when this new battery dies.