I have a 2018, and I replaced the brakes, and a bum battery. Drivers seat shows some wear with the fake leather interior, and I have some paint chips typical of bad primer used with white paint. Toyota won't cover the paint, but for me it is minor.
I get 20-21 mpg in the rural hills around here. With 115K miles it is in excellent condition. For me it is better than a pickup because I have a nice big aluminum trailer for hauling, and I like the enclosed back end of the 4Runner for every day dog hikes, and locking up rifles.
I tried trading it this year on the last of the 4.0 V6, and they would only give me 20K, so I walked. I think I can get 10 more years out of the 2018, so I am pretty content. Shame I have the cash from selling a Corvette and my Outback sitting in a CD.
The Highlander had had the same 2.4T since 2023, and the reviews on that engine are neutral. No mechanical issues so far, and about 1 mpg more than the 3.5L V6. I saw another 2.4T video from the toyota tacoma design manager, and he said the new 2.4T is about the same as the 3.5V6, but it saves the world by emitting less CO2.
So I don't see a consumer advantage to the 2.4T vs the 4.0/3.5 V6, with basically the same power and mileage.
For vanity I might get a new one in a year or two after the engine has been vetted. It would be real hard to risk a new platform with the 2018 being so solid. I even thought of a Tundra, but the SUV form factor suits me better.
2.4T highlander overview.
https://www.caranddriver.com/reviews/a43353345/2023-toyota-highlander-2-4-turbo-by-the-numbers/