Aren't Tesla already selling every vehicle they can possibly manufacture? With multi-month lead times on new orders? If they sat down and made the wipers and full beams perfect tomorrow, it's not like they would sell any more cars as a result.Tesla in the UK has to be a lucrative market but so many people who do love their cars comment about functions that don't work as expected or really are not fit for purpose, now I don't expect any company can make a product that is all things to all people but when the majority that comment identify something that doesn't function well or doesn't function at all you would think Tesla would be aware of this and take steps to address those concerns.
There is zero pressure on them to improve at present. I would imagine we will see little development effort put towards any features that don't take the company forward towards the mission it's set for itself (or resolve irritations that affect employees senior enough to influence things. Basically, if you want good wipers start praying for rain in California).