10766 and 7590 share source material but have vastly different purposes.
We must consider that a significant amount of time (9 years) has elapsed between their releases. These sets are made to appeal to a new generation of children who were not around when the 2010 wave was released. Also, the 2019 sets are made for the Juniors (or 4+) line. The sets are designed to be simpler and have large pieces so that younger kids can get into LEGO easily.
The 2010 set was made for the 20 USD price point and the 2019 at 10 USD. It is a lot harder to make an appealing set that can be sold at a $10 value because the budget is so limiting.
I don't own either set but the value on 10766 looks about right. It includes a couple highly specialized pieces, a couple of printed parts, extra accessories, and a desirable minifigure (I liked the moulded heads from 2010 but how LEGO has used minifig heads here looks pretty good to me). All in all, this set looks to have appropriate value and has great play possibilities for the very low price. If I were in the target age group, I'd think this set would be a lot of fun.
7590 was sold for twice as much as 10766. That means the designers had more freedom to include greater realism, detail, and more features (including minifigs). Not to mention that this set is not Juniors, but was actually recommended for ages 6-12, so its build could be more complex. Accounting for the inclusion of a pull-back motor, the value on this set also seems good to me. However, if you try to buy this set on the secondary market today, you will be paying a lot more than is reasonable for this set, compared to its objective value.
If I were given the choice between the two sets, I like 7590 better, but I can appreciate 10766. Overall I definitely prefer the 2010 lineup of Toy Story sets, but it is unfair to call the entire new wave a cash-grab. LEGO is taking the opportunity to bring new, younger consumers into their base, with sets coinciding with the release of a G-rated kids movie.
And, to bring things a little bit back on topic, there is a chance that, like Toy Story 4 and The Incredibles 2, either Minions or Trolls 2 could be a Juniors line. Therefore you wouldn't be the target audience and you have no obligation to buy the sets (you don't even have the obligation to buy sets if you are in the target market. One of the great things about LEGO is that it can appeal to vastly different audiences.)