The funny thing is that you absolutely can use LLMs to create or assist you to build new forms of automation and even symbolic AI systems.
These maybe more narrow / less general than agents but often more than enough for most tasks and problems. Best of all they're often deterministic and very performant in comparison to LLMs.
Games have been using these for ages for NPCs but they're not limited to those. Some examples: Utility system, hierarchical task networks, Goal oriented action planning, knowledge graphs and state machines.
Heck, need to translate or parse noisy, structured data like text, voice, images, video? Make the symbolic AI use self hosted lightweight LLM as a tool to translate it to symbolic form. No need for wasteful huge frontier models for that