ImageView with systemName partly blurry

The code that has the issue is this

ZStack {
    Image(systemName: icon.isEmpty ? "book.pages.fill" : icon)
        .resizable()
        .scaledToFit()
        .scaleEffect(2.5)
        .foregroundStyle(.ultraThickMaterial)
}

the book.pages.fill is completely blurry and the lung is partly blurred. If I remove the .forgroundStyle(.ultraThickMaterial) is is completely blurred. Some icons, tho, are sharp no matter the forgroundStyle is omitted or not.

COULD NOT UPLOUD IMAGE

Here is the complete code

import SwiftUI

struct FolderOverviewItemView: View {
    
    @Environment(\.colorScheme) var colorScheme
    @Environment(\.horizontalSizeClass) private var horizontalSizeClass
    @Environment(\.verticalSizeClass) private var verticalSizeClass
    
    var title: String
    var description: String
    var icon: String
    var image: Image? = Image("dummy")
    var color: Color
    
    var body: some View {
        Grid {
            GridRow() {
                Color.clear
                Color.clear
                Color.clear
                Color.clear
            }
            GridRow() {
                Color.clear
                ZStack {
                    Image(systemName: icon.isEmpty ? "book.pages.fill" : icon)
                        .resizable()
                        .scaledToFit()
                        .scaleEffect(2.5)
                        .foregroundStyle(.ultraThickMaterial)
                }
                    .gridCellColumns(2)
                Color.clear
            }
            GridRow() {
                Color.clear
                Color.clear
                Color.clear
                Color.clear
            }
            .frame(maxWidth: .infinity, maxHeight: .infinity, alignment: .topLeading)
            GridRow() {
                HStack(alignment: .top) {
                    VStack(alignment: .leading) {
                        Text(title)
                            .font(.headline)
                            .lineLimit(1, reservesSpace: true)
                        
                        if horizontalSizeClass == .regular {
                            Text(description.isEmpty ? " " : description)
                                .font(.caption)
                                .lineLimit(2, reservesSpace: true)
                                .truncationMode(.tail)
                        } else {
                            Text(description.isEmpty ? " " : description)
                                .font(.caption)
                                .lineLimit(2, reservesSpace: true)
                                .truncationMode(.middle)
                        }
                    }
                }
                .frame(maxWidth: .infinity, maxHeight: .infinity, alignment: .topLeading)
                .gridCellColumns(4)
                .padding()
                .background(.regularMaterial)
            }
        }
        .background(
            LinearGradient(gradient: Gradient(colors: [color.darken(by: -0.2), color.darken(by: 0.1)]), startPoint: .topLeading, endPoint: .bottomTrailing)
        )
    }
}