Tom does have a PhD in physics, so there is nothing wrong with Dr. In German-speaking countries in Europe (maybe others as well) it is a norm to put your degree in front of your name. If you rent an apartment your landlord will automatically put Dr in front of your name on the door-bell plate downstairs if you have a PhD (which you would have indicated in the application because it increases your chances to get that apartment). So it is a question of cultural background and since people on this forum come from all over the world, having rules or discussions about this seems meaningless.
Yes, of course, if he had his PhD, Dr. would be appropriate.
When this topic last came up for the wiki page, I was led to believe that he did grad school, but does not have the PhD, which in my field, is an indicator of common sense.
For those who have studied at this level, this is not a trivial distinction. There is great shame and loss of credibility if you permit someone to imply you have a credential that you do not have.
It is similar to the concept of stolen valour, when a military man implies he saw combat, when he did not.
The point is to protect Tom's reputation, not diminish him in any way.
Please cite your source and I will update the wiki page.