Yes it is. Pine needles make good mulch.
Down south, pine needles (also called pine straw) is used extensivly as mulch for trees, shrubs, flower beds and gardens. It is prettier and better than woodchip mulch because it will not attract certain bugs.
You can even mix the broken ones with your garden soil. They might be slightlt acidic but not much. By the end of the season, pine needle mulch will be broken and can be mixed into soil.
Use the top fresh one to mulch.

Pine needles form great mulch !

Just mix with other compostable materials in layers and you're good to go. Compost does best when there is an equal mix of greens (fresh plant trimmings, kitchen veggie trimmings and grass clippings) and browns (shredded newspaper, brown pine needles, fallen leaves, etc.)

Pine needles have a tough coat that will take a while to be broken down, much like oak leaves. That is why , fresh needle are suited for mulch and old ones as soil amendment and in composts. My native GA red clay garden soil mainly has been conditioned with pine needles, maple leave, oak leaves, wood ash, compost and leaf molds. This way I have made about 500 sq-ft garden area without buying anything.