No, powdered collagen provides the exact same benefits as liquid collagen for the same quantity of collagen consumed, and it is not diluted by water, offering better value.
Although some brands say that liquid collagen is more effective than the powdered variety, there is no credible scientific research to support this argument, which is simply based on misrepresentations of (1) what protein is, (2) of the manufacturing process for hydrolyzed collagen, and (3) of powdered collagens.
(1) "Liquid collagen" is simply a marketing term—there is no such thing as liquid collagen. Collagen is by definition a protein and does not assume a liquid or solid state. Brands marketing "liquid collagen" are actually just selling collagen + water, and you're being charged for the water.
(2) Water is used in the manufacturing of all hydrolyzed collagens, during a process called hydrolysis. Hydrolysis involves soaking the collagen in a food grade acidic formula and enzymes to break it down into peptides (chains of amino acids) that are easily absorbed from the digestive tract. The water-based solution is then spray-dried, interrupting hydrolysis at the right moment, so as not to break down the collagen too much (e.g. into individual amino acids that would not be recognized by the body as collagen). Companies selling "liquid collagen" then simply have water, and often other ingredients, added to the powdered collagen.
However, water serves no purpose beyond the spray-drying step other than to make the powdered collagen practical to consume. Whether the collagen powder is combined with liquid in a factory or in your home makes absolutely no difference to how bioavailable it is. The only difference is that you are being charged more for less collagen if you buy liquid formulas.
We would prefer let you add your collagen to whatever liquid or food you please, and not charge you for water.
(3) Brands selling "liquid collagen" claim that powdered collagens contain filler ingredients. This is not the case for Landish collagen, which is 100 percent pure hydrolyzed marine collagen and is of the highest quality, made in Canada according to industry best practices, with absolutely no fillers of any kind. Ironically, water is the "filler" used in so called "liquid collagens".
Finally we'll add that (4) "liquid collagen" products are almost always made from bovine or chicken sources, which involve questionable global sourcing practices and are much less desirable than pure, Canadian-made marine collagen. Learn more here.
Comparison
We combed the web, and found that the average serving of liquid collagen contains ~2.5 g of hydrolyzed collagen (~112 g in total), whereas Landish's Canadian marine collagen contains 8.33 g of hydrolyzed collagen per serving (250 g in total). When it comes to the benefits of hydrolyzed collagen, more is more impactful (up to 10 g per day)—the research proves this.
Most liquid collagens are sold at a premium, thanks to the magic of marketing, but even when they appear slightly cheaper per serving, you're actually paying significantly more per gram of collagen, making powdered collagen a better buy.