The simplest explanation is that it's chaotic damage from whatever overzealous autocensorship systems they have. The extent of the damage is moderated based on who you know - whether it's social media reach to someone employed there who knows the strings to pull, pay to play line to an account rep, or even ahead-of-time "this needs to be protected" due to threats/back scratching from/of the regime.

At least to me, this is a good working explanation - the conspiracy angles prove things that don't need to be proven to effect sustainable solutions. The real issue, as it has always been, is that we need to move away from these centralized communications technologies controlled by corpos. Their concentrated power is what makes their censorship inevitable.

So pragmatically as things stand - while it's completely understandable that political campaigns (and everyone else) need to engage with where people are, they should also be making it a point to nudge followers to distributed forums. Use censorship-eager popular forums to recruit new followers, but maintain your base of members with censorship-resistant communication methods.

Or politically, assuming a critical mass of people frustrated at this problem that we can effect change, what we need is anti-trust enforcement that breaks up these companies into smaller entities, chiefly by un-bundling apps (client software) from hosting services and mandating published APIs for the two markets to interact.