A Lambda printer is a giant of a machine which most people would not be able to find room for in a domestic setting. It takes 50" wide roll paper and uses its lasers to expose silver halide paper, which is then passed through a conventional wet process development and fixing. You would need, at least, a double garage to house it.
All of which is why there are only a few labs that offer this service, usually by asking clients to upload their files and returning the prints in a tube.
I think you have misunderstood what Lambda printing involves and costs. From Harman, a 20" x 24" print only costs around £30. See their site for more details
https://www.harmanlab.com/page/86/NEW-B-W-PRINTING-SERVICES.htm
Don't forget that we are not necessarily talking about a digital capture, it's the process of getting a print from a negative or transparency.
There is every bit as much an art form in carefully crafting a digital scan into a file that will be Lambda printed on silver halide paper as there is in producing a darkroom print on silver halide paper through an enlarger or contact print.
In the darkroom you use multigrade paper and filters, test strips and create a printing plan and dodge and burn with paddles to achieve an optimal print. On a computer, I use a calibrated screen and software to dodge and burn areas of the image in exactly the same way to create a perfect file that will then be printed.
Ian and Martin have provided all sorts of tutorials on what they refer to as "contrast grading" but is, in fact, dodging and burning.
Indeed. I have done darkroom printing - I needed to create a darkroom, either temporary or permanent, and spend hours and, more importantly, a lot of money producing test strips, printing plans and trial prints in order to get something that approached what I wanted. Now, I waste the same time but nowhere near as much money, as I am able to create a perfectly worked image for only the cost of the electricity to run the computer. Then it's a case of pressing "print" for a digital print, or sending the file to Harman for a silver print, knowing that, most of the time, that is the only time I will have to spend out on printing.
Of course, another advantage of the hybrid approach is that I don't have to go through the entire multiple exposure process that dodging and burning from a printing plan involves, all over again for every print.
Is digital printing of scans an art form? Well, if you consider that some B&W prints I have prepared have taken 3 or more days to work on, adjusting, assessing, leaving overnight for consideration and reflection, reworking, etc., it's certainly nowhere near an instant process and, as Ian, Martin and others here will testify, it's far from the everyday simple process that calling it "just digital" would infer.