Following PR #13511 it appears that there is not reference benchmark for SVMs in scikit-learn or in any side-project (sklearn-contrib).
This seems quite risky on the long run, maybe we should create one - especially to quantify the impact of changes to C code such as in PR #13511 .
I have been working quite a bit on this topic of creating reference benchmarks in the past years, leading to the creation of tools in the pytest ecosystem: pytest-cases and pytest-harvest, with a beginning of tutorial here (outdated I'm afraid). I can therefore certainly try to help with a benchmark framework structure if you find such an idea interesting.
However I do not know a good set of reference datasets to start with (apart from creating challenging ones "by hand").