Is it worth it to sacrifice some performance in return for a slimmer, lighter and cooler laptop? Not to mention a slightly cheaper price? I'm looking to make the most out of my purchase, say the option with the higher-performance-per-dollar ratio, so is a laptop with GTX 1650ti Max Q more worth it than its non-max Q counterpart?
Slimmer does not always equal to better since you will need to factor in heat dump by said innards/hardware. The trade off is that if you want sleek and minimal, you will need exotic materials to cool your hardware to maintain favorable temps(if it's to reside on your lap at all) or you go for a thicker form factor and work with off the shelf tried and tested cooling solutions with readily available materials. The same theory applies for the automotive sector.
The answer to your question will be possible once we know the SKU's to said laptop considering that not all laptops are made equally and not all laptop's employ the same cooling solution, not to mention that not all laptops are priced the same with variances in regional pricing as well.