In the article in question, which is paywalled, the call is made to either replace Hare-Clark with single-member preferential voting or to switch from five seats of seven to seven seats of five.
7x5, a zombie bad electoral take
Seven seats of five is an old chestnut that was roundly disposed of during the process of restoring the House from 25 to 35 members. As the concept of restoring the House to 35 seats gained traction in the 2021-4 term there was some support for doing it by going to seven five-member electorates instead of going back to five seven-member electorates. There was at the time only one Independent elected as such in the parliament, so the main motivation was to make things hard for the Greens. Anyone who is remotely familiar with that debate would be aware of the TEC's discussion paper that showed significant problems with the 7x5 model. One thing wrong with it is that it would require Tasmania to uncouple from the federal electoral boundaries and have its own state electoral boundaries process at an expense estimated at $2.5 million plus $300,000 per election. Being almost as large as the federal divisions and overlapping with them extensively the state boundaries would then cause a lot of voter enrolment confusion; the TEC also suggests it would be difficult to avoid severely splitting up communities of interest by drawing a line through Hobart City. (This said, it would get rid of the across-river divide in Franklin for state but not federal purposes, and drawing the boundaries of Clark in a completely sensible manner is getting more tricky anyway; more on this down the track).
