I haven't used an Air for development, but I do know that its power supply is 30w instead of the MBP's 100w. That's a big difference. Beyond the CPU's official specs, I'd bet some throttling happens there.
That said, I recently upgraded to a new MBP because my 2013 MBP had gotten really laggy for certain things, particularly the web (and the inspector, etc.). This was weird, because on pure-compute tasks it still did pretty okay. But basic sites like Twitter were visibly laggy, and the Chrome debugger was like mud.
I did some research and ended up concluding that it came down to the integrated GPU. The processor itself was still significantly faster than a brand-new Air, based on benchmarks, but integrated GPUs have made huge strides in the past 5 years (and web pages have gotten significantly heavier) and I guess that has a more noticeable impact on basic tasks than the CPU does.
Anyway. If you're only doing the occasional, light web dev then I would guess you'll be fine. It'll be noticeably slower than your 2017 MBP, but probably still passable.
That said, I recently upgraded to a new MBP because my 2013 MBP had gotten really laggy for certain things, particularly the web (and the inspector, etc.). This was weird, because on pure-compute tasks it still did pretty okay. But basic sites like Twitter were visibly laggy, and the Chrome debugger was like mud.
I did some research and ended up concluding that it came down to the integrated GPU. The processor itself was still significantly faster than a brand-new Air, based on benchmarks, but integrated GPUs have made huge strides in the past 5 years (and web pages have gotten significantly heavier) and I guess that has a more noticeable impact on basic tasks than the CPU does.
Anyway. If you're only doing the occasional, light web dev then I would guess you'll be fine. It'll be noticeably slower than your 2017 MBP, but probably still passable.