Arctic dev here. Yes keeping all experts in memory is the recommendation here and understandably that is a barrier to some. But once you have 1 H100 node or two (gpu middle-class I guess...?), then a few things to note:
1. FP6/FP8 inference is pretty good. How to on a single node: https://github.com/Snowflake-Labs/snowflake-arctic/tree/main... (vllm support coming soon!)
2. Small number of activated parameters shine in batch inference case for cloud providers.