For me
80s/Early 90s cars: Nice to admire from afar but a nightmare to keep going. They are cars I experienced as a kid. My grandfather had a Beetle, My dad had some V8s and an Alfa or two... I had fun with my Beetle project but I wouldn't do something similar again from that era. Parts are harder (or more expensive) to come by too.
Late 90s/Early 2000s is a sweet spot as mentioned above. You could buy one of these to mess about with and as your fun car. It felt like it was "yours" too in the sense that it was very easy to experiment and DIY things etc. Part of the reason I love my Cayenne is that I can run RCAs and have my wireless carplay and fill it with whatever I want to without worrying about coding/updating modules/injecting FSC codes/fooling systems etc. We have gone too far from that perspective.
I love (obviously) cars up to around 2020. There is a good mix of tech and safety and I definitely disagree that there is no fun or no soul to be had. Maybe if you were driving the wrong cars. These cars would save you if you were being a moron and save themselves (for the most part)... but they were not nannies.
As for cars since then? The pendulum had already started to swing too far for me.
I am literally sitting here as we type now
There are BMWs that I genuinely like... recently driven M3 Touring, M4 Cabrio and G99... but all of them have the trading desk screen and whatever you want to call this crap. Apart from being distracting, it feels cheap and literally looks tacked on with visible supports/brackets that even the dodgiest of audio installers would hesitate to put into a car... but everyone is very amazed by yet another screen in their lives or another app or another distraction - anything to stop them from experiencing the moment or engaging with the world around them. Heaven forbid we are bored for 2 minutes at a traffic light.
An E39 M5 has gauges and buttons that are like a fine vintage timepiece... There is something special about it even if it is old and there is more effort in making it as well. I can put a vintage-look face on a smartwatch but it will never compare.
Because the average person is so focused on the big screen, manufacturers take advantage of this big singular focus/distraction and get away with enshittification of the rest of the vehicle. Junk-tier plastic (eg X3 and any merc up to around R4M), disintegrating rubber bits long before they should (G20, W206), the basically universal worsening of carpets, plastic "leather" meant to make you believe it is 'green or vegan' while charging the same as leather (Mercs of all kinds are the worst offenders). I could go on and on... but suffice to say THIS is what we are also experiencing and while we are talking about dynamics and simplicity, there is a level of quality that an E46 or E39 (or W204 for that matter) had that you now only find on much higher end models or even in different (more expensive) brands.
I say this with an E39 touring in my garage now that I would very generously describe as 'mid-tier shitbox' grade that somehow feels better put together and higher quality than a brand new X3 that is LITERALLY 16 TIMES the price. Go figure.
Rinse and repeat for so many cars. The last I managed to stomach has been the F90's "analogue look" gauges with a couple of faux-metal inserts near the clocks. Downgrades for me in terms of 'specialness' from there with not only all-digital screens but also 'nodules' and notches that house things to monitor you. Like could they not find better ways of integrating these things? 992.2 Porsches have a digital dash that has not been well received despite not being as bad of an execution as BMW.
Anyway back to BMW, they had peaked with ID7 and now (like Microsoft and Apple) are changing things for the sake of it. Like many things it is devolving. It isn't working for me and with things costing what they do, it is tough to force yourself to both have to stomach the outside of a thing as well as the inside of one.
In tech we have had planned obsolescence for years (in various forms eg support being withheld, licensing, stopping updates etc), 'as a service' models where you don't own anything "and that's a good thing (TM)" and just plain FUD (Fear, uncertainty and doubt) used to sell/market the latest and greatest. The same is being applied to cars now with ever more complicated things that you never have to worry about as long as you are perpetually buying the latest and greatest... and for absolutely no good reason because a car does not disintegrate at 100000km or 100000 miles for that matter. This is just what the trade evaluator and sales guy will tell you as they take your paid-off time bomb off your hands and sell you the latest thing... I mean it is amazing - look how much bigger the screen is than in your shitbox timebomb

(just don't look anywhere else too closely)