As a requirement for getting regulatory approval to launch your satellite, I think you have to submit a debris management plan, which can include raising a geostationary satellite to a graveyard orbit after EOL (GEO is really far from earth, it would take a lot of fuel to de-orbit them), or lower a low-earth orbit to an altitude at which it would decay in a few weeks or years.

Generally, I think these small satellites are quite cheap both to launch and manufacture, do not have a great lifespan, and certainly not have lots of fuel. So they are most likely intended for LEO, and a low one with that, where atmospheric drag is small, but could bring a satellite down in a few (~5-7) years. Hopefully smaller than the rate at which the operator renews them.

Picking LEO has many benefits: lower latency, higher bandwidth, smaller antennas, higher resolution for pictures, with a few drawbacks: more earth shadow, faster ground velocity, smaller coverage for earth sensors.