Simple web CRUD WebFlux application: how can Netty be useful?

Question

I learned from here: What's the difference between Jetty and Netty? Netty is not a server at all. but from here: https://stackoverflow.com/a/57297055/10894456 I see it's the server.

Anyway I guess to run a web application there should be a server. So does Netty help to solve it? Or anyway need some kind of server ( Tomcat or Jetty or whatever)? But from here: Don't spring-boot-starter-web and spring-boot-starter-webflux work together? I learned Netty is not compatible with Tomcat...

Clarify please, what is the easiest way to create a reactive WebFlux crud application? How can Netty helps? What would be the server in case of using Netty? How Netty is compatible with it?

Edit: Ok, I see Netty is not a server by itself, need to write something like:

public class NettyServer {

    private int port;

    // constructor

    public static void main(String[] args) throws Exception {
 
        int port = args.length > 0
          ? Integer.parseInt(args[0]);
          : 8080;
 
        new NettyServer(port).run();
    }

    public void run() throws Exception {
        EventLoopGroup bossGroup = new NioEventLoopGroup();
        EventLoopGroup workerGroup = new NioEventLoopGroup();
        try {
            ServerBootstrap b = new ServerBootstrap();
            b.group(bossGroup, workerGroup)
              .channel(NioServerSocketChannel.class)
              .childHandler(new ChannelInitializer<SocketChannel>() {
                @Override
                public void initChannel(SocketChannel ch) 
                  throws Exception {
                    ch.pipeline().addLast(new RequestDecoder(), 
                      new ResponseDataEncoder(), 
                      new ProcessingHandler());
                }
            }).option(ChannelOption.SO_BACKLOG, 128)
              .childOption(ChannelOption.SO_KEEPALIVE, true);

            ChannelFuture f = b.bind(port).sync();
            f.channel().closeFuture().sync();
        } finally {
            workerGroup.shutdownGracefully();
            bossGroup.shutdownGracefully();
        }
    }
}

But I also believe literally noone do this when creating a simple WebFlux CRUD service. So still the issue: How can Netty helps? What would be the server in case of using Netty? How Netty is compatible with it?

Edit 2: after hours of browsing I realized: Netty - is not a server, it's just a framework using cahnnels/NIO2, but spring-boot-starter-reactor-netty offers non-blocking and backpressure-ready TCP/HTTP/UDP clients & servers based on Netty framework. But can use spring-boot-starter-tomcat, spring-boot-starter-jetty, or spring-boot-starter-undertow instead in this manner:

<dependency>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-webflux</artifactId>
        <exclusions>
            <!-- Exclude the Netty dependency -->
            <exclusion>
                <groupId>org.springframework.boot</groupId>
                <artifactId>spring-boot-starter-reactor-netty</artifactId>
            </exclusion>
        </exclusions>
    </dependency>
    <!-- Use Jetty instead -->
    <dependency>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-jetty</artifactId>
    </dependency>

So just 2 concepts are confusing and mess each other: Netty and spring-boot-starter-reactor-netty