Sea grass should be able to stick out of water and slow player movement

As known through the requests of the community, many of the subordinate water-related biomes such as beaches, rivers, and swamps need much improvement. A way to improve the swamps and shores would be to allow double-tall seagrass to grow/spawn in areas where there is only one block tall of water. This would primarily improve the appearance of the swamps and shores as it would allow seagrasses to reach above the water into the air block above as grasses do in real-world swamps and shores.

An interesting and useful mechanic out of this could vary boat speeds and even swim speeds when in seagrass. When boating through water such as a swamp, the boat speed could be slightly decreased if the water block below you is occupied by sea grass and even further decreased if the air block above the water block you are in is also occupied by seagrass in the case that a double tall seagrass grew/spawned sticking out of the water.

This mechanic would make navigating swamps and rivers more realistic and engaging and it would also allow for unique uses elsewhere such as boat racecourses. This change would only require 2 simple game rule changes and would keep the simplicity of the game while allowing for more complex opportunities.