Oh really? out of the original cast at launch, how many had significant mobility (non-ultimate dashes/blinks) built into their kits?
3 of 17
Compared to now where it's about half the list. However I concur that riot's design philosophy changing in season 3 was a major cause to the growing problem.
Indeed and they were early game bullies, bullies existed in every class & position; but the games lasted long enough for them to fall off. Not to mention riot has repeatedly buffed marksmen in the past 2 years to the point they're rarely weak at any point.
Not playing this game as much as I used to, I prefer strategy in team games, something riot has been removing for several years. Both directly (see the increased gold value of minions), and inadvertently (changing the way a turret's damage scaling works). I used to play around a dozen a day back in season 2 & 3, now maybe 2 or 3 games a week.
There was a brief time marksmen were replaceable, and it was finally interesting to play. It was a mistake giving marksmen spam-able mobility (see lucian & kalista), or excessive safety (see caitlyn & corki before and after the marksmen update). It's no wonder they don't need peel anymore, with damage and mobility creep being so out of hand, it ends up being pointless to peel; because the carry gets blown up before you can stop the enemy, or the enemy is so far behind that they get killed by the minions trying to reach your carry.
Towers haven't been that threatening for some time either, riot's been nerfing defenses (both of turrets & champions) since the beginning; most people don't understand the difference between buffed damage, and nerfed defense. They put a damage cap on towers years ago, sure they have built in armor penetration, but that does nothing against anyone with lifesteal. Hence marksmen & divers being better tanks than actual tanks. Not to mention tower ai-aiming has exploitable for years, and continues to after their updates; and with no utility to compensate for a lack of durability or threatening presence, they're basically just another wall to run around after the 5 minute mark.