That may be, but the Bolt isn't a road trip car — no Supercharger network — so it depends on what one is looking for.
People with Bolts have reported that there is enough fast charging available at least in California to support a number of different road trips. But the supercharger network is more extensive and the costs are more predictable than the charging options for the Bolt.
Unless Bolt sales really ramp up over the next year or so, I have a feeling Tesla will reach the 200K mark well before GM does.
The thing is GM sells a fair number of Volts in the US which count against the total. In 2016 the Volt was the #2 selling plug in car in the US about 4000 behind the Model S. In total sales of cars that count against the credit, I believe 2016 was the first year Tesla led the pack. GM has been top seller most years since the credit began, they have a number of cars that count against the credit for sale in at least some states.
Tesla might end up going past 200K a quarter earlier than predicted, but it's pretty clear GM and Tesla will run out about the same time. If the Model 3 is the success it looks like it might be, that puts GM in a difficult spot. They won't be able to produce EVs in volume to meet Tesla's production and they won't be able to fall back on the tax credit either. Effectively GM will have a price hike on all their EVs right at the time overall demand goes up.