Probably because the "Swiss model" is in flux. DW said
After four years of hard-fought negotiations, Switzerland has shrugged off a deadline for a treaty with the EU. It is concerned that freedom of movement requirements will flood the wealthy country with low-wage labor.
FT said
Swiss politicians resent what they regard as “blackmail” by Brussels [...]
The EU has granted the Swiss an extension of sorts to figure it out. That sounds somewhat familiar...
In the recent past, the Swiss were able impose some temporary immigration quotas on some EU countries (mostly newly admitted members); a few of these quotas are still in place. However it seems the new (draft) deal EU-Swiss doesn't allow for that. There's still some wiggle room in it for Swiss preemption for "at risk" jobs, itself a hard-fought issue in the negotiations. But this must look like a rather weaksauce solution in the UK given the hardline "take back control of our borders" stance.
DW suggested a mutual wait-game of the Swiss and the UK:
[T]he Commission [is] wary of going easy on the Swiss for fear of providing ammunition to Brexiteers. Meanwhile, many Swiss are happy to wait and see what sort of deal the British can extract for themselves out of the EU.
According to the FT article, in the new Swiss-EU deal there will be some role for ECJ e.g. with respect to state aid. An EU law blog explains how that can happen:
The [Swiss-EU] FA [draft Framework Agreement] rules on dispute settlement generally follow typical standards of state-to-state arbitration in public international law, with the exception of disputes where the interpretation of EU law is at stake. Notably, the chosen framework for dispute settlement is exclusive for both parties concerning interpretative disputes (Article 9).
To briefly sketch the procedure, if the relevant joint committee cannot find a solution to a dispute, after three months the EU or Switzerland can ask for the establishment of an arbitral tribunal. If the dispute raises a question of interpretation or application of one of the norms of the FA, the covered agreements or a referenced EU legal act (as provided for in Article 4 (2) FA), the arbitral tribunal turns to the CJEU [ECJ being the supreme instance of that], if the interpretation of that norm is relevant to resolve the dispute and necessary to enable the tribunal to take a decision (Article 10 (3) FA). The judgment of the [EU] Court binds the tribunal. [...]
The FA tribunal system is extremely closely bound to the CJEU, which in turn makes it politically very difficult to sell (in this case in Switzerland).
So the Barnier slide (which dates from a year before the draft EU-Swiss deal) is somewhat out of date. The new deal puts the Swiss in less clearly separate bucket from the rest of the EEA with respect to the "red lines" in that slide.
An article in the Economist written before the Swiss draft deal noted:
As far as Brussels is concerned, [...] Norway is treated as a friend—unlike Switzerland, which in place of the EEA has a laborious set of bilateral deals. The EU hates the Swiss set-up, because it is not dynamically updated to changed single-market rules and there is no agreed dispute-settlement mechanism. Diplomats in Brussels are clear that the Swiss model is not on offer to the British (many say it would not now be given to the Swiss).
And indeed the old Swiss model wasn't offered to the Swiss anymore (in the new draft framework deal).
In contrast the "Norway model" (EEA) appears more stable, so that's probably a reason why there is less reluctance to talk about it.