I think you're correct at a high level, but there is also the medium-term and long-term impact of not honouring treaties which is less predictable and makes the calculation around not honouring a treaty less straightforward (even if in the immediate sense the drawbacks are minimal).

WW1/WW2 also had their fair of treaty violations. Sudetenland annexation is an early example. Nazi Germany breaking the Molotov–Ribbentrop to split up Europe with the russians is perhaps a better known example. Italy was also supposed to join the central power in WW1 as per their treaty examples.

While long term impacts are always difficult to quantify by definition, they do have impact on how people think (especially people in power).