"Won't buy you too much more" is complete nonsense. Let's look at low end and high end starting attending pay and set them as $200,000 and $400,000. Obviously there is lower and higher, but this is a good guess. Then let's look at resident intern year pay and assume it's approximately $60,000.
Even if you're single and in California (worst possible tax outcome) you STILL take home $132,000 compared to $46,000 as a first year resident. Quite literally THREE times the take-home pay. If you're in Texas instead, and married? $158,000 versus $51,000. Again, THREE times the take-home pay.
But that's the low end of starting pay. Let's instead look at the $400,000 situation. Single in Cali? $237,000 vs the $46,000. Over FIVE times the pay. Texas and married? $301,000 versus the $51,000. That's SIX times the pay.