It's not I who doesn't like sequences so much as the ISU. Why do they have that 20% penalty in the first place? Do they think that combos are harder and they don't want skaters to wimp out with mere sequences?
Yes, they think combos are harder.
This year they changed their mind half loops between multirevolution jumps and decided that those should count as combos and get full value after all.
So ignoring the half-loop case, sequences happen in three situations:
1) The skater needs to connect the two main jumps with hops or one allowed step because the nature of the second jump is such that it doesn't take off from landing of the preceding jump.
2) The skater chooses to connect the two main jumps with hops in between because s/he is incapable of doing the second jump directly from the landing of the first jump.
3) The skater intended to do a true combination but a mistake on the landing of the first jump caused the way the jumps ended up getting connected to meet the sequence definition and not the combination definition.
3) is obviously not what the skater intended, but it does happen. You can see why the ISU would believe that that should be worth less than a true combination, GOE reductions aside.
1) and 2) are choices that the skater makes to maximize the number of triple jumps (and double axels) without having to do a triple jump directly from the landing of the preceding jump. Because, for the most part, they're easier than true combinations.
The ISU's thinking seems to be that the benefit of doing either combinations or sequences is the opportunity to fit a higher total number of jumps into the 7 or 8 allowed jump slots and that there shouldn't be yet another reward for doing combos; since sequences are easier than combos, they should be worth less.
Personally, I disagree and think that combinations should get a bonus, at least to the second jump, and sequences should get full value.
But I don't think the ISU had any intention of minimizing the number of jump sequences because they don't like them and want skaters to plan true combos instead. The rules have allowed a maximum of three combos
or sequences since the mid-1990s and require repeated jumps to be performed in combination
or sequence since the mid-1980s. Those rules didn't change with the new judging system.
What they have done is spell out the definition of a jump sequence much more specifically than the loose understanding that applied in the past, so a lot of what used to be considered jump sequences would now count as two separate jump elements.
Maybe a compromise would be something like, you are allowed one sequence at full value but the 80% rule applies to all others.
If sequences get full value, then combos should get bonuses.
At least that would be something for the tech panel and computer program to figure out and the skater wouldn't need to worry "does that count as a combo or does it use up my allowed sequence? should I change my plan on the planned sequence later?"