Can a Quality Full Range Speaker be the Limiting Component in a system?

Sometimes I wonder if people deeply steeped in this hobby haven't studied the trees for so long that they forgot they're in a forest. 
Given all the variety in speakers, space demands, and people's tastes, any speaker could be a bottleneck in the wrong room to the wrong person. I'm always surprised how much emphasis people put on gear upstream of the amp. Everything behind the speakers has but one simple job: to drive a load. The amp by far has the roughest job. 
Good sources are nice, but no source will make up for a speaker that cannot behave as required according to space and tastes. The speaker has to at least be capable of performing the desired task. The amp must be capable of driving the speaker to it's potential. The rest of the chain just needs to do it's simple job well and drive a fairly benign resistive, maybe mildly capacitive, load. I'm not sure any shortcoming between a source and pre-amp could compare to the shortcomings possible between speakers and an amp. 

You have received some very thoughtful answers through which I have learned some things here.   In my experience, outside of differences in speaker quality, amp/speaker compatibility issues, and sonic preferences of the listener, the bass response is the most difficult to get exactly right and (for a given speaker) is the parameter most influenced by the room.  Therefore, depending on the speaker and the room, I can envision conditions where a quality full-range speaker could indeed limit performance of a system.
I recently improved the sound of my system by switching from near full-range speakers to large stand-mounted speakers (two 9-inch woofers in each sealed box) along with two high-quality powered subwoofers.  This set-up provides a more consistent bass roll-off above 40 Hz (due to the sealed box), better overall integration of bass in the room (due to the superior control of the dual powered subs), improved bass definition, and overall lower frequency extension to below 20 Hz.  The ancillary benefit is slightly better clarity through the midrange.

One last point.

For some perception is reality.

An obvious after the fact result occurred following some of my previous steps up the audio finesse ladder as more costly items arrived replacing former old friends.

The overall sound quality. The sonic presentations. All seemed to remain the same tenor. Resolution gains were made. Better imaging developed. Bass was more robust and defined.

However, the voice of the outfit seemed to remain pegged pretty much at one point along the accuracy to euphony line a dot or two on its warmer side.

None of my latter audio arrangements sat squarely on neutrality. The previous earlier versions were busting down the doors of uber analytical and detailed, ushering a migration towards or away from crtical incisiveness.

What I’m saying is I feel a person’s listening preffs, genres notwithstanding, stay put once they’re matured or achieved.

You like your steak a certain way. Your coffee just so. Clothes and shoes need a certain fit in form and fashion. Music you are paying for to hear repeatedly in your home appears no different. Speakers need a certain aire about them esthetically and sonically to be there in the first place.

It follows then, if a major speaker upgrade is perceived and transpires how is the significance of the exchange then quantified?

Consequently, there’s a real good argument for ‘we’, or ‘us’ being the true bottleneck.

Well, that and money. Maybe a wife’s acceptance factor too.

BTW… on the WAF aside, just include the cost of some very nice jewelry in your proposed speaker upgrade and your choices for speakers will increase dramatically. Or should.

Predominately though, its us or the lack of $$$ which limits a system in at least one or two very under appreciated contexts.

Butperhaps that’s just me.

I'm not sure where to begin...there are so many terrific responses and I'm learning with each one.

So rather than respond specifically, let me thank all that have posted. 

I wish I could have provided a more concrete situation and phrased the question better...perhaps that will come in time as I digest what you have already shared and reflect and process the points all of you have made.

Thank you.