Your example is from a high-value engine where the switch to proprietary alloys has significant savings in a jet engine.

ICE for cars? Do you think the same constraints apply?

No, but I think if material science improvements can be made in jet engines, there is no reason to think combustion engines for car are "complete" and nothing around them could be improved. They're much less expensive, but at a much larger volume, and they have at least a few decades of future - even if we assume all of the developed world moves to EVs in the next decade or so, which is unrealistic already, there is all of the rest of the world. Most African countries don't have stable power for all of their populations, EVs are simply not going to work there as the main vehicle type. Then add in trucks, where the weight of the batteries makes them impractical for heavy duty long distance trucking. There are improvements, but it will still be many years before they are available, and decades before they've replaced everything already existing.

    >  They're much less expensive, but at a much larger volume

It is precisely because they are much less expensive that they've reached a realistic ceiling of advancement. If you're going to produce an ICE that yields a 10% improvement in efficiency, decreased weight, increased reliability, decreased maintenance effort -- but at a cost of an extra $xxxx per unit, then it may as well never happen.

As a logical exercise, let's consider what are some of the top technological advancements in ICE and ICE drivetrain components over the last 20 years. CVTs? Nissan's VVEL? What do you think are noteworthy automotive ICE technological advancements we can look forward to in the consumer space? Where exactly do you see automotive applications of ICE advancing in the next 10 years?

On the other hand, it seems pretty easy to see the exact opposite with electric/hybrid drivetrains. Many innovations and advancements. It's also easy to see the roadmap for advancements (see what the Chinese are doing). Battery swaps? New chemistries? Solid state batteries? Compact axial flux motors? Faster charging electrical architectures? Endless space for technological advancement and growth because it's so early.