Of course batteries will progress every year, and vehicles will get better and more capable. GM has already said the 2nd Ultium plant (Spring Hill) will use different chemistries and processes than the Ultium 1 (Lordstown) so they are planning continued development.
Its like an iPhone, you need an iPhone and buy one knowing next years model will be better in many ways. Same with an ICE car, they get more power, or better transmissions every cycle.
As for the 2026 HEV being more capable that is likely, but the jump will not be 2X or 3X, and likely not Solid State since that is not the direction GM is going .
If a car or any product meets your needs now and in the future it does not become obsolete, just that better is available does not make past products obsolete if they still meet your needs.