viability

As a professional software developer I have to say that's partially true, but don't devalue what an estimate does for us. Estimating projects is part of the job, and communicating that to customers with a worst case scenario estimate would still be great for everyone here. If they thought it would take 9 months to develop, communicating that it will take a minimum of that time would give us as customers enough to know that we need to find a different solution in the meantime. There's a lot to Data Merge and I'm guessing that the company wants to be sure they get it right and don't miss the vital features, so maybe getting an estimate isn't super easy at this stage in time, but if they have a decent scope they could easily throw out "at least a year" or similar vague estimates.

Another +1 for data merge, without it I will continue using scribus with python and bash scripts that are merging in data for my board game design I love Affinity Designer and the publisher beta had me excited, but didn't do what I needed it to.