Some certifications are super fast, some are super slow. It depends on so many factors… here are some reasons:
- different teams have different resources. The manufacturer may have put more resources or priority on this, or they may have resources better suited for this type of effort, or they may have resources with history on this work.
- different products have different histories, platforms, etc… some devices may be built on platforms that are easier to make “Roon Ready”, or the designers made decisions during development to make it less time-consuming, or they based these products on platforms they can reuse.
- the devices could have started development long ago, but you are just now hearing about it
- unforeseen issues could have arisen due to the quality requirements of Roon Ready, and the team was unprepared to deal with them
- the manufacturer deprioritized the work or something else jumped to the forefront of their attention
- … and many more reasons…
As for the Arcam, I can’t say what’s taking so long, because I don’t know which of the above (or other) reasons apply to the ST60.