The answer, of course, is YES they can. In my perfect world of mathematics education, no pre-school child is ever exposed to a worksheet of any kind. I would swing my magic wand, all worksheets would disappear, and the memory of them would be gone forever. In the real world, I know that simply won’t happen. There will still be some parents who will insist on using worksheets.
Teachers and parents basically are the primary users of worksheets. It is an effective tool in helping children learn how to write.
Both lower-level-thinking worksheets and too many (even high quality) worksheets can hold students back by not providing stimulus and challenge. Studies have shown for years (just do a Google search!) that children learn best through active involvement and real-life experiences. Virtually every teacher knows that children learn to read by being exposed to books and by being read to, NOT by completing worksheets. The same applies to all areas of learning.