Normally one can find a dealer a few miles away so this is a matter of, say an hour's delay in the morning. But if the dealer is 50 miles away and you're driving in the rush hour this may be a whole morning wasted.
Looking at twitter accounts and consumer reviews, the problem is much worse if, when the car goes wrong, you can't contact Tesla because they won't reply. Taking real examples, you now have a Model 3 with, say, a serious crack in the large rear window which is a safety issue. Or a display which keeps going blank so you don't know what speed you are going. If you are driving on business, you want the issue dealt with immediately, just like a normal ICE dealer repair. If you phone a Mercedes dealer, you'd expect the service team to reply within a minute or two, or if they are busy, phone you back.
The problem seems to be that Tesla are not good at responding to service issues. Yes, once one has a courtesy car, one can relax to some extent as one is still mobile. However, it isn't the new car you have leased/bought and customers generally don't want substitutes.
Good points which must effect the more junior managers and smaller company managers choices as they will often be dependent on mobility to execute professionally and have a home life as well. I would imagine these folk would want a S or X if they are going electric, the 3 being a bit down market.
For more senior folk in bigger companies, senior civil servants etc, it likely has limited effect as they would often be considered too valuable to be allowed to use business time driving themselves and would instead have a bunch of chauffeur on call as needed while they would be expected to get on with reading, making telephone calls etc while being driven about.
The Tesla model is to operate with out dealerships and instead have a network of authorised or Tesla owned workshops whose job would be to fix, if possible cars at an owners convenience where ever that may be, or otherwise bring a loaner and take the motor for repair. A broken Tesla will in general tell the Tesla network it has broken and inform them of the likely problems, such that Tesla will be aware of the problem before the owner calls in. It remains to be seen if this dealer free idea works in practice. For now it has teething troubles but in principle it gives a lower cost base to Tesla and if it can be made to work offers savings for them over having a dealer network.
For people who have been used to a dealer network, the Tesla model may be a step too far, especially has it goes through its teething years, but the history of the internet has been the decline and fall of many middle players as illustrated by the vanishing of second hand book stores from many of their long time locations and similarly in many other business.
The big question is: "Do we now need car Dealers?"
If I had to guess I imagine they will go the way of second hand book stores. One can argue it won't be so based on the success of Apple stores, but there are not that many of them and most folk are becoming more apt at sorting out Apple product problems by themselves and are becoming happier to buy things without first holding them.