Yes, I would agree with that. However I think the best way to do a series hybrid is with a battery large enough to do most of your normal driving, with the gas engine being a “range extender” - something to get you further if you don’t have the ability (time, or access to charger) to recharge the battery.
When road tripping you might find yourself using the range extender quite a bit. During normal use, not at all. And that “inefficiency” is probably fine in this case. Because, from what I’ve found with just 10 months of EV ownership, the EV is not a cost effective way to road trip anyway. Cost of electricity out-and-about while road tripping easily exceeds what I would pay in gas for our CR-V Hybrid. But charging from home beats the price of gas by 4:1, easily. Maybe more.
(At lunch today, because I have EVgo credits, I fast-charged. I added 20% to the battery at $0.59 / kWh. This is not cheap! Almost 6X the cost of electricity at home. That price is break-even with a 15mpg car. At-home prices is break-even with an 80mpg car!)