Of course, you'll get a bit more out of them if you convert your EPUBs to KEPUBs with Kepubify[0], but the point remains that Kobos are supplemented by their cloud/connected features, not inherently dependent on them.
When I bought the Kobo Clara it was also a significantly better device purely on hardware specs. It was slightly more expensive, but that’s more than paid for by how long it’s already lasted me, whereas my spouse’s kindle (bought before we discovered Kobo), is already e-waste.
Kobo has also officially tied up with iFixit to provide official fixing guides and parts, allowing for relatively inexpensive hardware repair (to be fair, the battery replacement process I went through my device was quite annoying due to the waterproofing layer, but it worked, and my device is much older than their iFixit partnership, so hopefully the newer devices have repairability more in mind).
It’s amazing to check out a book from your library and have it sync to your kobo, all paid for with your library card
You literally would have to pay me to go back to a Kindle
In fact all Kobo e-ink devices, except the Kobo Mini, wifi, and the original one, are still getting firmware updates.
Their android-based tablets with IPS screens are all discontinued though (as far as I am aware).
This is more than Amazon ever did. They haven't updated the firmware on some of their devices that are officially "supported" in years.