I have used the beautiful Olympus OMD E-10 Mk.III -- can't really say if it's going to be allowed in a concert[0], but it has a great advantage: it looks like a retro camera, and many people actually think it's an analog (ie, physical film) camera. I absolutely loved it's low light performance, though I've seen review compare it to the Sony A7 family and it'd seem those surpass it.

Before getting it, I owned two compact Canons, the G12 and G16 and both were a joy to use: fast stabilized lenses, """large""" sensors (at least for a compact camera) and lots of integrated features. The newer lineup has sort of derailed and there are tons of very-similar-with-tiny-differences models, but you'd be looking at either the G1X Mk2 or the G7x Mk2 (those are the ones that look more like compacts rather than "pro" cameras).

[0] since it's a mirrorless, so some would say a pro camera, hence not allowed without a permit.

The Sony Rx-100 mk V or mk VI will suit your needs perfectly. It’s pricy but generally considered to be the most camera you can pack into a compact. The VI has the only 35-200mm equivalent zoom on a compact which makes it perfect for sporting events and concerts that don’t allow ‘professional’ dSLR cameras.