Modular chains are much Adaptable with reference to speed of execution, specialization, and throughput. What they discuss much less is the strain such designs put on data availability when systems grow. Execution may be high-speed and graceful, yet it can only be as decentralized as it is in the conditions of multiple independent actors being able to access the same data, concurrently, without being coordinated off the protocol.
It is there that ills creep in. Systems do not stop when the availability is unable to keep up. They are narrowed to those that can validate, trust a small group of well-provisioned operators or add trusted relayers to buffer accessibility. These are not design failures, they are the logical outcome of considering availability as something assumed and not engineered.
Walrus is given by virtue of the fact that modular execution forces this tension to occur. It considers availability of data as the levels of infrastructure execution should be capable of reasoning about, rather than praying will be true. After availability has been synchronized and implemented at the protocol level, modular designs prevent performance-trading with decentralization.
That is what modular chains do not discuss on an adequate basis - and that which Walrus is constructed upon.
