It could be a different variety of Polystichium but I do not believe it to be P. acrostichoides.

I'm going to guess... P. setiferum (Soft Shield Fern):

https://plants.ces.ncsu.edu/plants/polystichum-setiferum/

https://www.monrovia.com/soft-shield-fern.html

This guess is mostly because I think that I found it growing wild in NC, and it's doing OK in the sun. As it gets warmer it'll probably struggle a bit in the sun, though, regardless of the variety.

Polystichum setiferum is not native to anywhere in the US so unlikely to be found growing "wild" anywhere here. If a wildling, I think the fern in question is one of the Dryopteris or wood ferns, several species of which ARE native to NC.

Oh, I thought the NCSU site implied that it was native to NC! Oh well.

Here's where it gets tricky...

The former homeowners built a garage next to a slope to the North, but they didn't allow for drainage so the soil on the North side of the garage is ALWAYS shady and wet. Their solution was to mulch it and forget it.

When I bought the place I was unaware of the drainage problem, so I removed the mulch and the hostas they had planted, then sowed grass and mowed over it.

A few years ago, I saw this fern growing up in that location. Instead of mowing over it I dug it up to see what would become of it, and it grew up to be pretty!

Now. Did a seed blow in the wind and land here, with no other similar looking ferns nearby? Maybe. Or is it something they planted, and I just kept mowing over it without knowing it? Maybe.

I looked at a few fern genera, and Dryopteris looks close, but the photo isn't clear enough to see important details, like the pinules, so if you can get a macro shot of the pinna and pinules, and also when ID'ing ferns it helps to see the backside of the frond to see what the sori,(spore cases) look like.

Here are some zoomed-in shots of the front of the frond, I'll take some more pics tomorrow (Sunday).

I tried to get a close up of the pinna, but there are other fronds in the way so it's hard to be clear:

Looking at Dryopteris varieties, I came across the Dixie Wood Fern that looks similar:

https://www.perennials.com/plants/dryopteris-australis.html

https://plants.ces.ncsu.edu/plants/dryopteris-australis/

Mine's nowhere near 4-5' tall, but the shape and color match. If I need to brace for it to be that size, though, then it'll definitely affect how I place it in the garden!

These are from the back side of the fern. In the first pic you can see a new frond starting to uncurl at the base:

Polystichum proliferum?

I do see similarities!

https://en.wikipedia.org/wiki/Polystichum_proliferum#/media/File:Gardenology.org-IMG_2352_rbgs11jan.jpg

But if I'm reading correctly, it's only found in the wild in Australia? I'm in the eastern part of the US.

UNLESS the previous home owners really did plant it, and it just survived being mowed over for years before being discovered. Based on the location, I can't rule that out!