A system can hold any properties it wants, as long as it stays fully self-contained.
In crypto, an elegant way of defending system properties in a self-contained way is by having a store of value asset as the central product.
However, systems with products beyond SoV assets don't stay isolated. They interact with each other via (product) features.
In crypto, systems might interact to on-ramp funds. Assuming this feature tries to on-ramp from tradfi rails onto e.g. Ethereum Mainnet, two systems with different properties collide. Then, either the feature gets removed (over time) or properties of either/both systems change. There's trade-off.
Sure, one could argue that there could simply be feature interaction between systems with very similar properties but I doubt this will get us very far.
My personal takeaway wrt recent debates is that there's a real possibility to strongly defend core Ethereum properties but it will likely require a much more self-contained system. If Ethereum wants to thrive via features, there's going to be inevitable trade-off wrt properties.