One very important fact about bitcoin is that it allows you to take responsibility for your own finances.
When the banks tell you that you need them to keep you safe, you do, if you can’t take this responsibility yourself.
Personally, I would rather be responsible for myself than accept all the baggage that comes with believing that I am unable to do so.
However, there are people who need to be protected from themselves making mistakes, and the banks are there to take care of them.
As a practical matter, I would never transfer more than a few hundred dollars in bitcoin without sending a very small amount first to verify the address I want to remit to… Then I can be very confident if I copy and paste that same address for the larger transfer. This verification is worth the cost of one extra transfer fee of maybe $10
I didn't try the BTC-Koolaid and along with my strong belief that banks and the financial sector has to be regulated (by something other than a paper tiger) I have these doubts about BTC:
1) The transaction overhead in terms of energy is very high - a problem for everyone but especially for a company trying to make the World sustainable - also wrt. PR,
2) BTC may not formally be seen as a currency, regardless it certainly has the equivalent of currency risk (and a lot of it too),
3) Faced with currency risk Tesla's accumulation of BTC can only be interpreted as their belief that it's value will go up - i.e. it's an investment bet, something which seems unrelated to Tesla's business plan,
4) Some BTC proponents like to contrast BTC with 'fiat money' - forgetting the fact that the government that backs its 'fiat money' has both an army for external threats and tax collectors (also ultimately backed by state-sanctioned violence). Compared with that, a crypto-currency is the ultimate faith-based (i.e. fiat) money, it is nothing but an algorithm and some open-source software with the support of no one,
5) A government will legislate to protect itself and to some extent the state and sometimes also its citizens - and passes laws it sees fit for this purpose. Such laws include 'legal tender' laws that heavily regulate methods and mediums of payment. As such, BTC has the risk of being outlawed (regardless of what many voters may prefer) if it is deemed too much of a competition to the legal tender (e.g. triggered by a loss of VAT revenue),
6) Because of their nature (see 4) - anybody can come up with a crypto-currency - so in that sense it is a bit like a pyramid-scheme, if you start one you make off like a bandit and if you come in late you end up as a bag-holder. So there is the risk to BTC that some competing crypto-currency (maybe a less energy-intensive one) will take away its market-share - which is one reason why there are so many crypto-currencies,
7) Although BTC is seen by some (and you seem to be included) as a way to revolt against the established, state-backed monetary system, it is entirely possible that a state will introduce its own crypto-currency, not just because of several of the preceding arguments, but also because it has the potential to lower transaction overhead. This increases the risk that BTC becomes out-lawed or out-competed,
8) As for transaction cost, Tesla's introduction of BTC seems to be a solution in search of a problem. I paid my Model 3 with a bank transfer - which EU regulation mandates must be free of a fee (which it thus was),
9) There are additional arguments against BTC, such as it being very popular among Internet-scammers - and the question, why should widespread adoption of this payment system make some unknown person(s) 'Satoshi Nakamoto' into what is likely a trillionaire? For the people objecting to the current financial system, that's just like toppling one dictator just to put another one into power.
I will not be disappointed if this post is moderated away, my point being that it is just too easy to formulate a lot of critical questions regarding BTC - especially in relation to Tesla.