You know what else Fighters don't get? As many class abilities as every other noncaster.
Really, I'll never understand why people keep bringing up the number of ASI a fighter gets like it's some sort of saving grace. They're not free by any stretch of imagination, they replace actual class abilities, and depending on the class ability and the specific feat we're talking about, ASI/feats are not bound to come out ahead.
Also, spending a feat/ASI just to increase a single save by a single point is a terrible investment, and fighters only get 2 extra ASI anyway.
Fighter: Fighting Style, Second Wind, Action Surge, Indomitable, 2*ASI Bonus, 3*Extra Attack, 5*Archetype Feature
high hit die, all weapon proficiencies, all armor proficiencies; no tool proficiencies
Barbarian: Rage, Unarmored Defense (only provides an alternative to armor proficiency and is redundant), Reckless Attack, Danger Sense, Extra Attack, Fast Movement, Feral Instinct, Brutal Critical, Relentless Rage, Persistent Rage (not an actual ability, just removing a penalty for losing rage), Indomitable Might, Primal Champion, 4*Primal Path Feature
highest hit die, all weapon proficiencies, medium armor and shield proficiencies; no tool proficiencies
Monk: Unarmored Defense, Martial Arts, Ki, Unarmored Movement, Deflect Missiles, Slow Fall, Extra Attack, Stunning Strike, Ki Empowered Strikes (not an actual ability, just removing a penalty against some opponents), Evasion, Stillness of Mind, Purity of Body, Tongue of the Sun and Moon, Diamond Soul, Timeless Body, Empty Body, Perfect Self, 4*Monastic Tradition Feature
average hit die, simple weapons+, no armor proficiencies; proficiency in one artisan tools (or musical instrument)
Rogue: Bonus Skill Proficiencies, Expertise, Sneak Attack, Cunning Action, Uncanny Dodge, Evasion, ASI Bonus, Reliable Talent, Blind Sense, Slippery Mind, Elusive, Stroke of Luck, 4*Roguish Archetype Feature
average hit die, simple weapons+, simple armor proficiency; proficiency in thieves' tools
That puts them at...
Fighter ~18 (2 given for the better armor options, 1 for all weapons, 1 for high hit die)
Barbarian ~19 (2 given for highest hit die, 1 for all weapons, 1 for armor, none for unarmored defense as redundant or persistent rage as simply losing rage less often)
Monk ~20 (none given for ki empowered strikes)
Rogue ~18 (1 given for light armor assuming DEX build)
It's debatable on the value of each ability and more after looking at how often each can be used, but there doesn't appear to be a big deficit for having selected a fighter when looking at other non-casters as you have stated. A person shouldn't just look at activated features in such a comparison.
Also, "only get
2 extra ASI anyway" is massively underselling the benefits of ASI's. When feats are allowed (normally IME) that's 40% more than most characters get and that's at 19th level assuming no lost last ASI to multiclassing, in which it's 50% more than those characters. Feats are pretty potent in 5e.
Actually increasing ability scores often isn't as effective as using the ASI for a feat, but in a featless game it's definitely worth it to invest a few build points in WIS and then some ASI's because after CON and attack ability score that's still going to give bonuses to important skills and WIS save, and there isn't going to be anything else on which to spend said ASI's outside of looking at such things.
I think you are over-stating the issue.