

You can always encrypt the payload twice if you want. But really what are you arguing? That every time you encrypt something, you should encrypt it serially with all known encryption algorithms “just in case?” Hell why not do it again just to make sure?
A key component of encryption is efficiency. Most cryptographic processes are going to be occurring billions of times across billions of transactions and involving billions of systems. It’s worthwhile for robust encryption algorithms to be efficient and avoid unnecessary calculations unless those calculations demonstrate some advantage. For example PBKDF2, where the multiple rounds of identical encryption convey a demonstrable increase in time to decrypt via brute-force mechanisms. If the standard is 4096 which it was in 2005, you coming along and saying, but why isn’t it 4097? The CIA is using >4096, therefore that means that 4096 is insecure! Isn’t really understanding why 4096 was chosen to begin with. Additionally no one is stopping you from using one million iterations with key1 and then doing another million rounds with key2.
Well I haven’t see the arguement for why Quantum resistent encryption would somehow be weaker to traditional cryptographic techniques. I understand that early “quantum encryption” alogrithms were flawed, and it’ll probably be a long time before we get the DES of Quantum Encryption. But all that means is that we don’t have vetted “strong” quantum encryption techniques yet, and should stick with traditional encryption since quantum encryption isn’t worth it yet. If Quantum encryption becomes worthwhile, we shouldn’t have “traditional encryption”, because it will be obsolete.
If the first cylinder lock was easily bypassed compared to my old reliable wafer lock, then why should I use the cylinder lock at all? Now that cylinder locks are better then wafer locks why should I use a tumbler lock at all? There is no added security by using a wafer lock.