The tire business can be a brutal one - low growth, low margins and extreme competition. Tire makers are at the mercy of ups and downs of raw material prices...
Large flat roads are also more efficient. Have you ever driven down a bumpy road? That shit aint efficient. All of your horizontal speed gets turned into vertical speed in a jarringly unpleasant way. That’s part of why trains are so efficient because their tracks are so smooth.
Large wheels have nothing to do with a vehicles ability to go off road/on bumpy roads, if anything they’re counter productive because you want large soft tires and small wheels for that scenario.
Large flat roads are also more efficient. Have you ever driven down a bumpy road? That shit aint efficient. All of your horizontal speed gets turned into vertical speed in a jarringly unpleasant way. That’s part of why trains are so efficient because their tracks are so smooth.
Large wheels have nothing to do with a vehicles ability to go off road/on bumpy roads, if anything they’re counter productive because you want large soft tires and small wheels for that scenario.