If we’re already making changes, then we should also change the rule that it is permitted to eat a regular meal outside the sukkah. Nowadays regular meals are also commonly eaten outside the home in restaurants, which in the past was very rare (people mainly ate at home or at a friend’s home, but not in a place that wasn’t a home and where no one lived). The same might apply to sleeping: nowadays it is common to sleep in hotels, which in the past was also rare. Maybe what can remain is the existential commandment—meaning that if you stay in a sukkah, there is a commandment in that, but there is no prohibition on eating and sleeping outside the sukkah, just as nowadays it is not unusual for people to eat or sleep outside the home.

Besides that, you wrote that this can be changed—did you mean that one can already issue such a halakhic ruling for oneself now? Or is some kind of consensus or something else needed for the change to take effect?

That is indeed a sound argument. Except that one must consider whether a restaurant/hotel itself has the status of a home, in which case one would need to go out to a sukkah from the restaurant/hotel. That is not comparable to travelers on the road, whose very definition is being outside the home.

I think one can rule this way for oneself. But without consensus, I would do so as a stringency, not as a leniency.

As for a restaurant, I think it does not have the status of a home, because no one sleeps there. Even in terms of civil law, it is considered commercial space and not residential space (with implications for planning and construction, municipal taxes, etc.). As for a hotel, that may indeed be more problematic.

Regarding ruling this way for oneself: do you rule this way for yourself? And if not, why not?

A restaurant is a home for eating, like a room in one’s house. But as I said, there is room for hesitation here.
I do not rule this way for myself, because I also eat even a casual meal in the sukkah. But if there were some need to give up this stringency, it could certainly be considered.

Rabbi Yoel poured out his pain here
http://www.maalegilboa.org/article/%D7%9C%D7%99%D7%AA-%D7%90%D7%AA%D7%A8-%D7%A4%D7%A0%D7%95%D7%99-%D7%9E

It is hard not to identify with what he says. And one can add to what is written there the bad custom common among the public not to bother reciting Grace after Meals even after eating baked grain foods in a quantity that satisfies, when one is then obligated on a Torah level according to all opinions.
But in my opinion he is completely right also regarding one who establishes his meal on meat. And those "who fear Heaven" and are concerned would do well to eat a piece of bread so as to recite Grace after Meals and fulfill the obligation of “and you shall eat, and be satisfied, and bless!”—a full obligation that the Sages and the Shulchan Arukh cannot (and Heaven forbid did not try to) uproot.