I don't agree with that assessment. Fisker recently dropped all solid-state efforts, stating that it's a Uber-hard nut to crack. I believe the specific sentiment was that they quickly got to 90% of where they needed to be, and then realized the remaining 10% was more work than the previous 90%.
We'll see solid state battery tech, eventually, but even optimistic estimates have it 5 years out; conservative estimates are even further in the future.
Some people will be able to buy a R1T and will trade it in on their second before solid state batteries see widespread consumer use.
The key lesson is that there is ALWAYS new tech "around the corner". Faster, stronger, lighter -- whatever. Buy when you're ready to buy. You're probably going to be in the market, again, in 3-10 years, anyway, right?