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Yes in 2026 but I guess it's not useful since you can use your phone connection.
Some Plans/carriers are better suited to data, some for cellular. For example I have a pre-pay sim that gives me 750GB a year for around $60 - it's convenient not needing to tether (which some companies do not even allow depending on the plan and device).

Also if memory serves correctly you need the cellular iPad for GPS purposes.
 
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