It's an uphill struggle, but let's try to re-inject some sanity into this debate.
1) Part of the reason the "game the system" brigade have become so militant is because they've genuinely convinced themselves that the list vote system is some kind of conspiracy to reduce pro-indy representation. As I pointed out in my recent National Extra piece, that simply isn't the case. Both the SNP and the combined pro-indy camp are in fact slightly over-represented in the Scottish Parliament as compared to the votes they received in the 2016 election. The purpose of list seats is to bring the overall composition of parliament more into line with the percentage of votes cast for each party - sometimes, as was the case in 1999, 2003 and 2007, that leads to a correction in favour of pro-indy parties, and sometimes, as was the case in 2011 and 2016, it leads to a correction in favour of unionist parties. But whichever way it goes, the effect of list seats is always to make the result more proportional. In other words, to make the outcome fairer. There really isn't anything to be angry or concerned about in that.
2) The system is actually biased against one type of party, though - namely, very small parties. Almost every system of proportional representation around the world is intentionally loaded against tiny fringe parties - for example in national list systems, there's often a 5% threshold to attain any sort of representation at all. The Holyrood system achieves a similar effect by being conducted on a regional basis, which in practice ensures that any party will need 5-7% of the vote in a region before it will win any seat. So if you're thinking of voting for a small party, you need to be very hard-headed and realistic about its chances of securing the required number of votes. There may well be good reasons for giving your vote to a party that isn't going to win any seats. But if your main reason for choosing a small party is to "game the system" and to win a truckload of extra seats, your logic has gone wrong somewhere.
3) The only way to game the system is with a large party, not a small party. And the only way a "pop-up party" is going to be large enough is if it's fronted by Alex Salmond. I literally cannot think of any other person who is capable of pulling it off. I suppose it's possible that Dave Thompson's initiative today might be part of pre-planned choreography that is paving the way for a Salmond-led party. But if that isn't what's going on, Mr Thompson is just adding to the collection of very small parties who will be scrapping over the small number of people who want to vote "tactically". The more of those parties there are, the more distant are the hopes that any of them will win even one seat.
4) To the best of my knowledge, Alex Salmond has not publicly denied suggestions that he might set up a new party. That may or may not be significant. If he eventually goes down that road, I and many other SNP members and supporters will have a big decision to make. The reason for my current allegiance is that the SNP are the credible party that most closely represents my own views. That might no longer be the case if there was suddenly a Salmond-led party, which would almost certainly be somewhat stronger on independence than the current SNP leadership, and less obsessed with "woke" identity politics. But it would still be a very tricky decision, because I have fears about the long-term/medium-term consequences of fragmenting the independence movement. And I would always vote for a party on the list because it's my first-choice party, and not for any "tactical" reason.
5) If a Salmond-led party does not fight the 2021 election, the only other way of bringing about a stronger line on independence is to win the internal debate within the SNP - and the more people that desert the SNP to join fringe "game the system" parties, the less likely that is to happen. I firmly believe Colette Walker made a tactical mistake by leaving the SNP. It's less than a year since she almost won the Women's Convener vote, which meant that for as long as she remained in the SNP, she was a very real threat to the "woke" hegemony. By walking away, all she's done is help to entrench that hegemony - as can be seen from the jubilation in certain quarters on social media.
6) Jason McCann recently wrote a blogpost about the Holyrood voting system that was misleading or inaccurate in a number of respects. He stated that it was "a mathematical impossibility" for any one party to dominate the parliament - it "cannot be done", he added. That is simply untrue. If a party were to receive 100% of the votes, it would get 100% of the seats (as long as it put up enough candidates). There is no artificial 'cap' on the number of seats that the SNP or any other party can win. Jason conveniently neglects to mention that part of the reason the SNP lost list seats in 2016 is because its pecentage list vote fell. If you get fewer votes, you get fewer seats - it's not rocket science. On a point of pedantry, it's also wrong for Jason (and indeed the Solidarity account on Twitter) to refer to the Holyrood voting system as "the D'Hondt system". AMS is a hybrid system and the D'Hondt formula doesn't apply to all of it. It's ironic that the tactical voting lobby refer to it as "D'Hondt", though, because it's the very fact that it isn't a pure D'Hondt system that makes it (theoretically) suspectible to gaming.