It feels like you're trying to make the point that there is too much inventory - that cars are easy to get quickly because Tesla is not supply limited and inventory is piling up. Is that in fact your point?
The cumulative model 3's manufactured as of Q2 update letter was 291,173 while the cumulative deliveries was 276,098 so you are correct that there were 15,075 model 3's in inventory worldwide at the beginning of July. But here is the context for that:
We don't have sales numbers for model 3, but a proxy for that (which is pretty much guaranteed to underestimate it) would be:
Q2 sales = Q2 deliveries + Q2 in-transit - Q1 in-transit = 77,500 + 6028 - 8586 = 74,942 model 3 sales for Q2. Here I'm using 81% of total in-transit for each quarter since model 3 made up about 81% of total deliveries in each quarter. Q2 had 91 days, so model 3 sold 823 cars per day. With 6028 cars in-transit the "available for sale" inventory world-wide was 15,075 - 6028 = 9,047 but about 1,500 (my estimate) of those were aboard the GMT Astro bound for Tianjin, so only 7,547 were on-the ground. Realistically Tesla probably should keep at least 200 model 3's around for test drives so really only 7,347 should really be "available". That is less than 9 days of sales which is really too low of a number. Just looking at the whole 15,075 inventory that is 18.3 days of sales in the world-wide distribution pipeline, meaning that the curve of inventory/sales-rate that Tesla presented in the Q1 letter has fallen substantially to it's lowest level in years.
If you are still worried about Tesla's inventory anyway then you should think that all other car maker's are on death's doorstep since they have much, much greater available-for-sale inventory/sales-rate than Tesla does.
Tesla does have an inventory problem. They don't have enough inventory because they are supply limited. The pipeline is underfilled, almost empty actually.