This is reasonable, though on the flipside, the commenter could also become stuck in a role at a large corporation where either the work is repetitive, or the skills are non-transferable to other companies (i.e. the work is highly specific to internal tools not used elsewhere), with no on-the-job time to improve one’s skills.

You’re right that conditions could be far better for skill improvement, though having paid free time is also a great environment (e.g. for potentially earning a graduate degree online from a reputable institution).