Quite the contrary. If you look at the details, AM5 is as forward looking as AM4 was, so AMD can just improve using the same socket and just decide, strategically (like with AM4) which CPUs to move forward and when.
If you ask me, having more options is always a better business strategy than forcing your hand into a minimal set of options. Intel just decides to lock themselves in quick cycles for reasons, but given how the economy is looking, they may end up getting the short end of the stick* until the economy improves. Sure dual DDR support is good, but they'll be dropping that with Meteor Lake, or so it is reported. AM5 is just, right now, the better platform and it'll be supported for longer. From a consumer perspective, that's better. From a business perspective, that gives AMD options on how to segment their CPUs offerings and whatever technologies they want to include without forced segmentation.
Also, what makes you think Intel after Raptor Lake won't stagnate again? Look at the jump from Alder to Raptor. It's similar or worse than Zen1 to Zen1+ in terms of gains. Again, their new platform will be expensive, more so than AMD I think. By then, AMD will have some economy of scales with motherboard manufacturers, which Intel won't. That's also why the 700 series chipset is not that much more expensive that 600 series. Whatever chipsets AMD comes with later, will just get cheaper over time; more so than Intel's, I'm sure.
I'm not a business person and I can't quite predict exactly how things will unfold, but I don't think I'm too off the mark.
Regards.