There are a lot of proposed solutions to the current "Healer problem", but the fires of rage are burning now due to the solo TOP clear. There are many solutions that have been proposed for a while, but the important thing about solutions is that they address the problem they are being proposed to address.
What would prevent 0/1 Healer clears of on patch content?
1) More DPS buttons for Healers? Well...no. While this might address boredom, if people are clearing content without Healers, it's not (mechanically) due to Healers being bored.
2) More support/buff/debuff buttons for Healers? Probably not. Same reasoning; people are already clearing content without Healers, so more buffs/debuffs wouldn't likely change that unless they were explicitly made requirements.
3) More damage from encounters? Well...yes, but not in a vacuum. Specifically, the damage has to be something that Tanks can't cheese and Tank + DPS healing and mitigation can't heal through and that they need more powerful and/or more spamable heals (and thus Healers) to get through.
4) Less Tank/DPS mitigation? Same as (3), this is only a partial solution. Mitigation checks aren't healing checks. Simply removing the mitigation wouldn't work since encounter design would need to change to have SMALLER spikes (ones that can't 100% party members if unmitigated) otherwise they're automatic wipes. That or give the mitigation to the Healers...which could work, though it would shift more stress onto Healers. But that isn't inherently a problem.
5) Less Tank/DPS healing? Same as (3), this depends on the encounter design. The issue comes down to if Tanks/DPS can get through consistent damage over an encounter on their own healing or if they require the dedicated Healer tools.
6) Healer kits being changed? Same as (3), but also factoring in (4) and (5). The Healer kits as they are now are not why TOP was 0 Healer cleared (though AST's kit in specific is why the recent solo heal was possible...) Healer kit changes, like DPS and support options, are more a thing that has to be done after (or rather, factoring in) encounter design changes to work with the new paradigm produced is. Healer kit changes, alone, won't fix the problem, since again, TOP was cleared without any Healers at all.
The overall solution is probably a holistic one, but proposed solutions need to address the actual problem.
If the problem is (and it has been stated to be or include, owing to them being used as "evidence" in support of it) that 0/1 Healer clears of content are possible, then the solutions need to address that first and foremost. Further changes can be considered for other issues once that is resolved, but if that is the (near) universally agreed upon problem, then the solution(s) to it need to address that.