Late summer shedding in golden retrievers is totally normal and expected - they're basically swapping out their entire undercoat to prepare for cooler weather. Since your dog's three, she's been doing this cycle for a while now, so the timing tracks. Daily brushing (or even twice daily during peak shedding) actually helps way more than every couple days, especially with a breed that dense. A slicker brush or undercoat rake will pull out loose hair before it ends up on your furniture, which makes a real difference.
Here's the thing though: even though shedding this heavy is normal, it's still worth paying attention to whether the skin underneath looks healthy. If you're brushing her regularly and noticing any redness, flakiness, or if she's scratching a lot, that could signal an issue worth checking with a vet. Most of the time it's just the coat blowing out, but the shedding itself can sometimes hide underlying skin problems if you're not looking closely. Diet matters too - a good quality food with healthy fats supports coat health during these transitions, so if she's on something questionable, upgrading might help reduce the amount of breakage and overall shedding volume.
The shedding should taper off once fall really kicks in and her new coat settles. Until then, invest in a good vacuum and maybe throw a blanket over the couch.