I work for a global company (sells and manufactures globally) and it is very common for globally regional price differences well above currency conversions and tax differences. The reasons include but are not limited to different supply chain cost structures (a topic in itself), different local market objectives (local competition pressure, goals for market share or profit, etc), fixed costs differences (land, building, insurances, and more), and more.
There have been a few times in my career where we lost business in the US because a global customer price shopped and found a better deal by ocean freighting equipment in from Europe or Asia made by my company there. In other words, my company ended up competing against itself. And, the opposite has happened (equipment purchased from our USA office and shipped globally).
You suggest that price discrepancy among global regions should only be attributable to "any additional taxes or features." However, these are often the least attributable factors.
Maybe someday there will be a better "global price." However, that is nearly impossible today for complex manufactured items (without price gouging or operating at no profit in one market or another).
This is very, very different than dealerships in one jurisdiction selling vehicles above MSRP due to demand greatly outstripping supply. First, Tesla is selling their vehicles within each jurisdiction for the same non-negotiable price. Price increases are across the board in that jurisdiction. Rare, time limited price discounts are available to anyone buying and with the goal of maximizing production (not limiting production as a way to increase price/profit). Second, legacy auto MSRP's vary by global jurisdiction as well (for all the reasons I noted above). Third and as I noted already, even if Tesla tried to make a global price, for all the reasons I already listed this would end up over-charging customers in one jurisdiction in order to ensure a profit in Tesla's most costly jurisdiction.
I would also note that my company has never increased price because of temporary insufficient supply of our product. That practice actually violates our company's ethical standards and sales managers can be terminated for violating this. I will not go so far as to declare this universally unethical or morally objectionable, but it is not a fair business practice and this is why the legacy auto dealership's practice is so frowned upon by almost all consumers (except for the few with financial means who appreciate being able to jump to the front of the line by paying the dealership's mark up).