It's not "summer peak" -- For the last few years, mid-July to late September has been fairly soft. (especially from mid August)That's why they have almost always offered free dining in recent years -- Which turns into a huge discount, especially for families of 4+ with "Disney adult" children.
This summer, it's 25% with very limited rooms set aside for that discount, may resorts at only 15%. If you were to try to book now, you'd find very very limited availability.
Historical discounts for Mid July - September, courtesy of mousesavers:
This year: 7/11-9/29: 10-25% off
2020 -- some summer discounts were announced but Covid cancelled everything before Disney would have released their full summer discounts.
2019: (now getting into pre-Covid): 7/5-9/30: free dining. 5/28-8/28: 15-25% off (with more availability than this year) PLUS free gift card. 20-35% discount for AP holders, Florida residents, Disney Visa, etc.
2018: 8/2-10/7: 20-25% off. 5/29/18-8/25/18: partial free dining. 8/20/18-12/23/18: Free dining.
2017: 8/1/17-10/7/17: 15-30% off. (25%-35% for AP holders, Visa card, etc). 8/21/17-12/23/17: Free dining.
So 10-25% is on the "soft side" but it really becomes anemic when you see there are no AP/VIsa card discounts announced. No free dining. And there is very limited availiability for that 10-25% off.
Polynesian is currently excluded altogether.
Polynesian Villas are only 10%. (and Copper Creek is only 10%).
This is much smaller than you saw in the past. Where all deluxe usually got 20-25%.
Caribbean Beach Resort is only 10%, again anemic compared to the past.
Now check availability: I'll look for a week in late July:
Contemporary Resort: 0 availability, not a single discounted room
Beach Club: 0 availability, not a single discounted room available.
Grand Floridian: Outer building rooms available at 25% off
Boardwalk: Garden view rooms available at 25% off. No water view or standard view rooms available.
Yacht Club: No standard rooms available. Water view and garden view available with 25% discount.
Wilderness Lodge: "Fireworks view" only available. Quite overpriced if there are no fireworks: Even with the 25% discount, it's more expensive than the discounted room at Grand Floridian!!
So that's it, those are the only available 25% discounted room for the week of July 24-July 31st.
And that is not normal. That's far far less discounted supply than you usually see for summer.
It appears to be higher than normal summer occupancy rate, but that's partially due to many resorts still being closed. Surely, if they opened all their resorts, they would have a lower occupancy rate. But they have more than enough demand for the resorts that are open.