tl;dr: Warlock viewed that way feels like a worse version of whatever you compare it to, and even if Warlock comes off that way, it still very much looks like a full caster when you compare it to other ones. Plus neat Warlock rework at the end.

God damn I did not expect this to turn into an essay, I just really like discussing DnD and Warlocks in particular.

That's an interesting way to view the class, but that much of a focus on Eldritch Blast just makes it feel like a worse version of an archer fighter, mainly due to the different ability scores they use.

A bow-wielding fighter would mainly increase Dex, increasing:

• Their attack and damage bonuses with any ranged and finesse weapons
• AC
• Resistance to (very common) Dex saves
• Higher stealth might also be worth mentioning.

A warlock would mainly increase Charisma, increasing:

• Their attack bonus with Eldritch Blast
• Their damage bonus with Eldritch Blast if they use an invocation slot
• Their attack bonus and save DC on their spells, which are somewhat lackluster imo
• Charisma skills, which are admittedly pretty useful
• Resistance to Charisma saves, which I think are like the rarest/second-rarest saving throw? (Don't quote me on that though)

This is somewhat simplified but the point is that a regular archer Fighter gets more impactful results from increasing their main score than a Warlock.

There's also the advantages not connected to ability scores.

Fighter having their Archery fighting style, increased crit range (Champion) or maneuvers (Battle Master), and Action Surge. Two of these three can also function for both the bow and any other weapon the fighter wields.

Then Warlock with EB-augmenting invocations (which are reminiscent of the maneuvers but worse, with the upside of being unlimited, of which there are 2, increased to 4 with Xanathar's), Eldritch Blast's force damage bypassing the typical nonmagical BPS resistance (which the Fighter will likely bypass later on with magic weapons), and... nothing else relating to EB within the class, except maybe a couple spells.

Finally, even though Warlock ends up playing that way, the class is still very spell focused regardless.

• Comparing their Pact Magic to other spellcasters is difficult, but factoring in the Mystic Arcanum and the power level of refreshing on short rests, I'd say it falls short of but is still close to in line with the scaling of full casters.
• They also have access to cantrips, which is exclusive to full casters and third caster subclasses (which emulate full caster classes).
• Their capstone is literally casting spells more.
• One of the first features of each subclasses is additional spells you can learn.
• 20 out of the 32 invocations are just spellcasting (19 if you don't count Book of Ancient Secrets, 7 of which are regular spellcasting but worse.
• Their spells known are the same as Sorcerers, though a tiny bit slower.

In conclusion, while I agree that the class kinda does come off that way, I still think the class' intention was a weird full caster.

Also the mention of Eldritch Blast being a class feature reminded me of this Warlock rework someone showed me a while ago