so was it the acceleration that broke it?

It looks like you deleted your later post from this evening. Next time, please carefully consider the situation before you tell someone flat out "You Are Wrong" and whatever else you said to me about my ignorance.

So much confusion wrapped into a single post. It's glorious.

Thanks to the OP for returning and giving us the rest of the details. I hope Thule does the right thing and makes you whole regarding the bikes and the rack. I still can't believe the design of that support post with that huge diagonal hole through it. It's like cutting a 6 inch slot for a bit of plumbing in a 2x10 floor joist - you now have the equivalent of a 2x4 as a floor joist. Anyway, thank goodness you weren't cruising down the freeway at 70 with traffic behind you. Good luck.

You need to take GOOD quality pics of EACH item, especially where the break occurred, then bag and tag each item. Send ALL the pics to Thule, along with your damage claim. Do NOT send the broken items-they are your proof. Send an itemized repair claim, along with pics and weights of each bike. Looks like you have a valid claim here. I was just playing "devil's advocate", looking for all the things that they will be looking for.

Thule is sending me a check to cover the bike repairs and a new rack. Process was pretty hassle free. I exchanged a couple of emails, sent a few pics and a repair estimate. That's it. I did ask if the new Apex 5 still has 1.25" post with 2" adapter. Per Thule, "It’s still a 1.25” with the adapter, though the design and materials have changed so that this no longer happens."

I'll post again when I get it. But I'm very happy with how smooth and easy the process has been so far.

That's nice to hear. It's when things go wrong that you can really tell the true nature of a company. It looks like Thule passes.

FWIW, when I took a course titled "Design for manufacturing" required for my mechanical engineering degree, I doubt that a design such as this would get a passing grade. It's both elaborate as well as insufficient. Looks like it was designed by a committee.

But then, I may be prejudiced; I looked at racks a few years ago, and found Thule's offerings both overpriced and underwhelming, so I bought a Yakima.

best wishes, it could have been much worse

Now you've got me worried. I've been known to cram up to 7 bikes (albeit kids bikes)
onto this 2 inch hitch mount using a 1.25 adapter.
Also, I never imagined having to read a manual for a bike rack.