For the notion of Beerus being that strong, we have:
- The already mentioned Galaxy Buster statement from Piccolo.
- Toriyama implying Beerus could destroy the Kaioshinkai, which based on what guidebooks show of the scale of the DB Universe, could be a feat above Solar System busting.
- The recent universe statement from Kibitoshin.
- Toki no Kaioshin stating that Beerus may destroy all of time and space if angered in Xenoverse.
Most of these can be debunked however, with Piccolo and Kibitoshin's statements not specifying it to be just from one attack, much like how Goku said that the entire universe would be in danger if he didn't defeat Freeza. Aside from video game material being questionable, the Xenoverse one is likely also from chain reaction due to the characters being at the source of space-time during that part. The only evidence to imply Beerus is above Solar System level is Toriyama's statement, and with that, you have to call into question if a man who couldn't remember there was a Super Saiyan 3 is aware of the size of the Kaioshinkai.