Unless they were making money based on their proprietary modifications to Grafana, Loki, or Tempo, they aren't affected much beyond being required to publish links to the source code.
If, however, they _were_ making money off of proprietary modifications, and they wanted to keep such modifications proprietary, they now have the choice to fork Grafana (and Loki and Tempo respectively) as of a pre-AGPL version.
If, however, they _were_ making money off of proprietary modifications, and they wanted to keep such modifications proprietary, they now have the choice to fork Grafana (and Loki and Tempo respectively) as of a pre-AGPL version.