

Conceptually, LoL filled a hole. DotA was DotA, complicated, hard, lots of nuance. Some people wanted an even more complicated DotA. Heroes of Newerth filled that hole. Some people wanted a simpler DotA. LoL filled that hole.
I personally preferred HoN, but I can’t fault people for preferring LoL.
There’s plenty of stuff dropped, a lot of it is dubious tbh.
My older phones had: IR blaster for controlling TVs FM radio tuner Replaceable battery’s Headphone jack (as you noted) Expandable microsd storage Physical Keyboards (no real loss imo)
Probably some others I’ve forgotten. Honestly, I slightly miss the IR blaster on occasion. I haven’t listened to FM radio in ages, but could see it being useful. Replaceable battery’s would be nice from a longevity perspective, but I prefer battery packs to device specific batteries for longer life in general and battery life is more than a day for me anyway unless I’m going nuts. The lack of SD storage is the one that bothers me the most.
Keep in mind phones have gained at least a few things in that time. Simple reliable waterproof is a huge one.