Have they ever addressed what would happened to the app you build if their company disappear one day? It doesn't seem safe to build your system on Bubble or any SaaS for that matter unless you know the company will never go away e.g. Salesforce.
At least two of those (Budibase and Saltcorn) are available as one-click apps on DigitalOcean. Saltcorn has users with no coding skills who have done this, budibase probably does as well.
I have zero interest in running a hosting business
I could see that use case inside a business though, where your non-developer staff can build their own line of business apps and your normal ops people can deploy them internally. I guess the other tradeoff there is support though.
This would be my concern also, same as with other tools like repl.it, etc. But it could still be useful for a prototyping phase. (Potentially. I have not used it.)
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