It's not about the fleets it
It's not about the fleets it's about the routes. Fleets do need to be long range capable but I think, like regular cars, the majority of miles driven are short trips well within range of a single charge per day. So fleet operators with a standard mix of short and long range hauls will probably end up with a majority electric trucks and keep some internal combustion ones for the longer hauls. But even those will lose out. Crew rests are important and it's so hard to keep good drivers, if your fuel costs are a tenth of what they were before you can afford to pay your driver's more, give them more time to make the drive and charge and still save money. Argue all you want but trains are way slow and they still make sense.