I concur with most of what Rabbi Forst said and especially applaud his "elu v'elu" approach re: the respective roles of Jews and Gentiles in the world.
My post on Sukkah Sensitivity, supports a mildly higher level of interaction between Jews and Gentiles than does R. Forst's chapter. But this is but a quibble.
On this issue of interaction one may understand the Halachic restrictions as effecting 2 different positions. And perhaps both positions are equally legitimate, but would be applied differently based upon the circumstances "on the ground".
• Attitude 1 Complete "levadad yishkon"
Hazal have enacted rules not only to prevent intermarriage, but to avoid assimilation. Therefore, the ideal is no interaction at all. Exceptions are only made for absolute necessity.
• Attitude 2 - Raising Awareness
Aderabba, interaction is OK and at times desirable. Thus, the enactments of Hazal are really mnemonics reminding us to always be aware of our unique separateness lest we get carried away by being overly chummy. So these are g'zeirot keeping our natural friendliness from over-stepping boundaries that keep us as the am hanivchar. The g'zeiros are about engendering "mindfulness".
In our society, I would favour somewhere in the middle. Too much standoffishness is AISI counter-productive to being a positive influence. Yet with the rate of assimilation, a high degree of mindfulness must also have some "restraint" WRT even being overly chummy.
Tangent on Shemen AKu"M.
I never understood the need for hashgacha on Olive Oil due to the bittul of the g'zeira on Shemen AKu"M. R. Forst explained it simply.
The original g'zeira was about assimilation and was similar to Bishul AKM, Gvinat AKM
IOW it was about assimilation and had little or nothing to do with the actual ingredients. Now that the g'zeira has been rescinded, that is still true. Gentiles may produce Olive Oil w/o and Jewish Participation. Thus our Hashgachah today is ONLY about insuring no unKosher contamination via Ingredients or Keilim does not concern hands-on Jewish intervention.