Today, the majority of modern crossbows weigh between 5.4 to 8 pounds. Note that this is the weight of an unequipped crossbow. When you add optics, sling, and a quiver with arrows, and maybe some other accessories, that would be 2 or more pounds in addition to the weight of a barebones weapon. So on average, you are looking at a 9-pound fully equipped crossbow. For comparison, an equipped rifle usually weighs more than that.
Keep in mind that 10-15 years ago crossbow hunters had to carry a few pounds more as older models were heavier and not as efficient as todays. Now you can easily find a 5.4-pound crossbow that shoots 350-grain arrows at more than 300 FPS. And it won't cost much.
Here are some examples of crossbows that weigh below average, are well-reviewed, and are perfectly suited for hunting whitetail deer:
|Model||FPS||Weight (lbs)||Price (USD)|
|Killer Instinct Hero 380||380||5.8||$299.99|
|Barnett XP 400||400||6.2||449.99|
|Wicked Ridge Rampage 360||360||6||$459.99|
|Wicked Ridge Invader 400||400||6||$669.99|
|Excalibur Micro 360 TD||360||5.6||$1,099.99|
Of course, a crossbow that is lightweight and relatively cheap would mean some sacrifices here and there, but it would still be a deadly weapon that you can rely on.
Compared to a compound bow, crossbows look and feel quite a bit heavier and clunkier to lug around the woods. And the extra weight becomes more relevant with age of the shooter. A bow can be physically more demanding to shoot but are considerably more convenient to carry on a hike. Does that mean that the main advantage of crossbows (accessibility) is negated by their weight and shape?
In practice - not really. Unless your plans include long hikes or stalking.
In reality, the majority of bow and crossbow hunters prefer more stationary methods of hunting - either from an elevated tree stand or from some sort of a ground blind. That doesn't mean you cannot try more creative approaches, but these are the easiest and most effective ways to get back home with some venison.
This means that most of the time you won't have to carry your crossbow more than a couple of hundred yards at once - the distance between the spot you parked your car and the tree stand or the blind. And a sling would make this easier.
On the other hand, the weight of a crossbow can be detrimental to your accuracy if shooting without any support, i.e offhand. Even if you are strong enough, most crossbow models are not perfectly balanced for shooting this way - most of the weight is concentrated in the front half, where the riser, limbs, and the stirrup are. And this makes them more or less nose-heavy. Definitely not ideal for aiming.
To overcome this, crossbow hunters virtually never shoot without proper support. They either rest it on some solid object or use a shooting stick, or a bipod, or a tripod. And if there's nothing better around, your knee would do a great job.
So when you take everything into consideration, the weight of a crossbow is not that big of a deal. Especially in 2020-2021, when even the most lightweight models deliver plenty of power - enough to hunt large game like whitetails and wild hogs.
But at the same time, even a minor (temporary or permanent) injury can steal the fun from using a crossbow, so it may still be a factor you should consider before ordering your first crossbow.