You should be fine, depending on size. However, well known FMQ like Diane Gaudynski and Sharon Schaumber have made large quilts on older machines.

I had a Brother CS6000 and I believe that has a 6.5" harp. I FMQ stippling on a lap quilt and it was fine. Don't let anyone discourage you to try!

You can still do it but it will be more of a challenge. Just going to have to reposition it a lot and roll over the excess. I wish I had one with a bigger harp; then maybe I wouldn't have so much trouble FMQing.

I would encourage you to at least try it first. Don't let someone else discourage you before you even start. And start with something small, so you can build your skills. Once you have a couple of smaller projects under your belt, gradually move up to larger projects.

I will say that I started out by rolling my quilt up to fit it in the harp, but I really struggled with it, so I quit rolling it and started accordion-folding it instead. Worked much better for me.

It can be done, my domestic Singer has about that size. But I limit my quilts to "throws" only 48 - 54 across. It also works better if I do a meander and don't roll the quilt, bunch it up.

My 14 year old machine has a 7" harp. I have quilted a king size quilt on it by cutting the batting into 3 sections. I try to quilt all of my twin and smaller quilts on it. I am still learning FMQ; but I am great at doing my SITD with my free motion foot. Although I would love a 12" harp, I am doing fine with my little machine. Now, if I draw in the patterns, I do a good job of FMQ. My goal this year is to learn to do FMQ without having to follow lines. Practice on your machine. I am sure it will work well for you.

All of the above is great advice, I would also chose a thinner batting at first. Less to roll or bunch up.

I only have 7 1/5 and I've done FMQ on a full-size quilt.

Split the batting so it takes less room, there is a boofk machine quilting in sections, and Ann Peterson had a class on craftsy quilting on small machines. It is doable just need to be creative