I see the base of a tree on the left of your photo. Was this area previously under heavy shade? Is the soil naturally acidic? While all azaleas require acidic soil, they don't all require shade. Some, in fact, need sun. HERE is an article on the basics of azaleas.

As to rejuvenating the azaleas, you should fertilize right now with a fertilizer for acid-loving plants. Fertilizing is usually done in June, August and October, though that depends on how far north you live. Continue to water every 1 to 2 weeks if you don't get rain. Mulch with pine straw. Azaleas prefer well drained, moist soil, so you need to water accordingly. If your azaleas don't respond to the added care, wait until late winter or early spring before pruning. Pruning is done one of two ways: either cut back 1/3 of all stems, or remove 1/3 of oldest stems to the ground. Note that pruning all stems will remove all flowers from spring blooming azalea varieties.

I would try to provide morning sun (part shade, no more than 6 hours of sun) only or dappled sun plus well draining, acidic soil that is as evenly moist as you can make it. Lack of sunlight can produce long thin growth. Inconsistent watering can cause leaf drop and give the shrub a scraggly look too, So avoid periods of very dry soil, followed by wet soil, then very dry soil again, then wet soil, etc. If you have trouble doing that and the soil gets too dry or soggy/wet often, be aware that azaleas have very shallow, tiny, fibrous roots that normally grow about 4-5" deep. To get control of your watering, avoid using a watering schedule and instead insert a finger into the soil and only water if the soil feels dry. Do this often. If your soil has no nutrient deficiencies, I would not feed an established except to provide 3-4" or organic mulch year around. The mulch will act as food and protect the roots from temperature extremes in the summer and winter. Azaleas are not heavy feeders and established azaleas will feed off the decomposing mulch just fine. Some cottonseed meal (about one cup for a newly purchased nursery stock) or Holly-tone (per label directions) can be used at first in spring when the plants are not yet established. Do not feed them this late in the season. Although this varies by geographical location, consider applying your last fertilizer application three months prior to your local average date of first frost. Or apply fertilizer for the last time in July.

Information from the Azalea Society of America:

https://www.azaleas.org/wp-content/uploads/attachments/Azalea_Care_Flier.pdf

Have you seen these plants in bloom, do you like them? Azaleas respond well to rejuvenation pruning but on the other hand, these are small enough to discard and start over with plants you do like.

Just an FYI but according to the ARS (American Rhododendron Society), rhodies and azaleas are best served by fertilizing in late winter or early spring - February is typically mentioned - if they need any fertilizing at all. They are not heavy feeders and rarely require supplementation and can be adversely affected by fertilizing when not needed, so use a light hand. They also caution about fertilizing after June.

And like their rhody cousins, azaleas respond well to hard pruning. Hard pruning - cutting back to about 12 inches or so - stimulates the development of adventitious buds that exist just below the bark on any stems. But a hard prune may delay any flowering for a season or two as the shrub regrows.

Here, gallon sized evergreen azalea plants are a dime a dozen in spring and very inexpensive. You can often find them for sale at groceries stores for less than $10. Even larger and more desirable varieties available at nurseries and garden centers are relatively cheap and available in quantity. For more rapid gratification, I'd be inclined to rip out the existing ones and replace with fresh

Thanks for the great responses everyone. I'm leaning toward pulling them up and planting new ones in the spring. We just cut down a big tree that was keeping these from having much sun, so I assume new ones will have a less leggy shape.