I think I will finally be friend with NSAttributedString. This snippet uses _functionBuilder because I'm still running Xcode 12.4

AttributedString+ResultBuilder.swift

import UIKit

typealias StyleAttributes = [NSAttributedString.Key: Any]
enum AttributedText {
    case text(String, StyleAttributes)
    case image(UIImage, StyleAttributes)
}


@_functionBuilder
struct AtributedSringBuilder {
    
    static func buildBlock(_ texts: AttributedText...) -> [AttributedText] {
        texts
    }
}

func makeAttribtedString(@AtributedSringBuilder _ content: () -> [AttributedText]) -> NSAttributedString {
    let result = NSMutableAttributedString()
    for attributedText in content() {
        switch attributedText {
        case .text(let text, let attributes):
            result.append(NSAttributedString(string: text, attributes: attributes))
        case .image(let image, let attributes):
            let attachment = NSTextAttachment(image: image)
            let attr = NSMutableAttributedString(attachment: attachment)
            attr.addAttributes(attributes, range: NSMakeRange(0, attr.string.count))
            result.append(attr)
        }
    }
    return result
}

let image = UIImage(systemName: "lock.fill")!
let attr = makeAttribtedString {
    AttributedText.image(image, [.foregroundColor: UIColor.systemRed])
    AttributedText.text("Hello, World!", [.foregroundColor: UIColor.systemTeal])
}

print(attr)