As competitors either direct (like Polestar) or indirect (like ID3) start selling well, Tesla's challenge will be differentiating itself in a way that attracts buyers. As they've a very contrary way of doing things, then any one of those might be how it chooses to play, but that'll be what it needs to play on, simply "being" isn't enough.
I agree, and think that, right now, there are a proportion of Tesla purchasers who are buying the cars simply because there's nothing else on offer. If you're someone looking to either switch to an EV, or just replace an existing EV with another one, and you want to be able to drive more than a couple of hundred miles from time to time, then a Tesla was really the only option.
Tesla's key differentiation is with the supercharger network, the minimalist design of the Model 3 (that I think will become common to all Tesla models before long) and FSD. There will be some prospective buyers for whom none of those aspects of the cars are high on their priority list. In fact they may well actively put off some buyers.
As a case in point, I really loved the minimalist design of the Model 3 interior. It was one of features that really did swing me to order the car. However, having lived with it for a bit over a year, there is no way I would accept any design where form takes such precedence over function ever again. The very severe functional compromises that have been made to create that minimalist interior are, for me, a step too far.
Supercharging may or may not remain a powerful factor in future, it depends on the rate of development of other charging networks and whether or not the rumoured opening up of superchargers to other cars happens.
FSD seems a long way off, at least for the sort of roads I use most of the time. It may be that FSD starts to work well for roads like motorways before long, though, so for those who do a lot of driving on roads like that it might well become a significant factor. Whether we'll see FSD working adequately well on rural roads, or even in UK urban areas, remains to be seen. It seems probable that we'll see it within the next few years, but I have doubts as to whether cars being sold now will ever have a complete FSD capability. The progress being made by some other manufacturers seems pretty rapid, and, at least as far as UK roads are concerned, close to being as capable as AP.