Well, my aged 2014 15” 2.5ghz quad core 16gb ram 1tb was great until the last 2 years or so, when lots of safari tabs really choked it ip. It might have been my large photos library too (300gb, like 60k or more photos).
It can get very difficult to understand what limits your old computer and why it is lagging a lot. For some it is a slow hdd which could be remedied by the regular cheap ssd. For some it is a low RAM, while others are choked by CPU.
OCR heavily relies on CPU. I bet that your computer chokes because:
1) Your CPU is old enough at this point.
2) If your ssd was almost full, then that is the reason number 2. I mean if it was full for 80% or more, then it leads to the major slowdowns.
3) Given your use case, you were not limited by RAM.
I feel i kept it way too long and that ill be happier upgrading in 3-4 years max rather than as long as ive waited
Well lets face the reality. Your old 2014 MBP 15 is only twice slower than M1 Air both in single core and multicore performance. MBP 14 is 2 times faster in single, 3 times in multi. MBP 16 is 2 times faster in single, 4 times in multi according to geekbench 5.
What I am trying to say here is that in 7 years we got only +100% to the speed which is crazy right? I mean it is low and slow.
But I am 13 incher from 2012 coming to M1 Air - this thing is 3 times faster in single, and 5 times in multicore.
As a 15 inch owner, you didn't lose much by not upgrading all these years. If you were a 13 inch holder, then that would be another story.
I occasionally need to batch edit 4-500 photos at a time for quirky tasks: i convert books to pdfs: Photograph every page of the book, change the contrast, exposure, etc so that it is nearly black and white, and OCR/text recognize them in a program like abbyy and then make them into a single PDF with text file. That was also killing my last mbp the last few years.
I got the base M1 Air with 512gb. Recently i batch processed 1500 pages book, because I had pdf of it, but it wasn't searching for words in the document - it needed to be OCR'ed. So i did convert my pdf book into 1500 single TIFFs and then OCR'ed them all with 8GB of ram on m1 Air. It didn't take any longer than 15-30 minutes. Overall my laptop didn't even break a sweat.
Occasional lightroom, imovie, big photos lib, big music lib almost as big as photos lib, ms word, excel and ppt, safari, chrome firefox, hundreds of tabs, abbyy finereader and preview with like 20 pdfs open. I put lots of pictures in my word files. PDF files can get to 500mb easily, more often 1-250. The photos I start processing can be 10-12mb each for the batch photo editing. Sometimes this happens all at once if my schedules been chaotic and ive had to start and leave tasks on hold.
Then I might want to do sime simple video editing ontop of that, clipping and combining some 4k video.
Only 4k video with 3 heavy luts or layers of color grading will choke it. That is the point when you want to take a look at mbp 14/16.
If you ask me, from technical standpoint, M1 Air with 16GB of RAM and whatever SSD size you want from Apple refurbished will come even cheaper than the base MBP 14 and will handle everything you listed. Now that is a technical standpoint only. If you want (as a feeling, but not need) it(mbp 14), then you don't need this analysis and can buy the one you want, because even Air would be enough for your use case and MBP 14 is faster than Air.