Was waiting for someone to mention Lynxx. Have the same 2 saws you have, 6 months after I bought them they were discontinued, instant orphans. Makes me very hesitant to buy store brand battery tools in the future.
Not sure I'd call this a bait & switch, more like they were discontinuing a house brand and replacing it with a national one that at least once upon a time had a good reputation.
Lowes does seem quick to discontinue items, hand tools too. A few years ago they made a file handle to use with their own files that had 1/4" locking hex tangs. Thought it was a great idea, have never had good experiences with traditional file handles. Of course, they were discontinued too.
Uh, maybe because guaranteed you will get inundated with spam emails, not just from them but from everybody they sell your name to.
I'm of the belief that you shouldn't need to "register" a tool in order to get warranty coverage.