I feel like companies whose niche is tooling to analyze Google data are living on borrowed time as it is. I would assume that they would have some advantages beyond Google not being interested in their market, otherwise this kind of disruption seems inevitable.
I guess at least some of these types of companies are consultancy companies disguised as product companies? If that's the case they might not be affected too badly.
There is some truth to this, however Google Data Studio can also hook up to Postgres and Mysql data stores making it a bit more than Google-specific tooling.
