6 years to master a syllabic alphabet seems like a stretch...They seem to be crossing learning the language and learning the writing system.
I studied Greek and Hebrew in college, Latin in high school. In each the very first night's homework was to memorize the characters and their pronunciation.
Multiple ANE cultures used cuneiform (Ugaritic, Akkadian, Sumerian, Hittite, and so on). The time to master each depends on your native language, the target language, and exposure to similar languages. The writing system is not the hard part.
I studied Greek and Hebrew in college, Latin in high school. In each the very first night's homework was to memorize the characters and their pronunciation.
Multiple ANE cultures used cuneiform (Ugaritic, Akkadian, Sumerian, Hittite, and so on). The time to master each depends on your native language, the target language, and exposure to similar languages. The writing system is not the hard part.