I know of someone in their mid 40s who started at a major Irish low cost carrier not too long ago. He said the type rating and base training was incredibly tough and a big learning curve, but he managed to pass it without any issues. I know his course had a fair range of ages probably averaging out at the mid-late 20s.
For the OP, age 40 means you have a 25 year career ahead of you. This isn't the 1960s/ job for life era and in the modern world, that is a pretty long career. If it is truly your passion, I think some good advice has been given above. You've now got a valid IR so are close to the cockpit. Look at what's out there.
Some have said there will be no jobs in Europe for the next 1/2/4/6/1000 years, but this just isn't the case. Ryanair, Wizz, BA, flybe Jet2 are just a few of the well-known names I have seen recently advertising. The Sandpit hiring gears are also being oiled up. Yes, some, like BA and flybe, were for experienced pilots, but even there at least some of them will move from somewhere else opening up a position somewhere else.
I have noticed an uptick in FI jobs recently too. The flight school market seems to have rebounded quite a bit since when the pandemic hit. My feeling is a lot of students (rightly or wrongly) are anticipating 2022/23 to be good ones for the job market. Though nobody knows for sure of course.
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Nightstop I wonder what on Earth was going on at that low cost carrier if all over 35s failed their base training. My first thought is there must be very serious deficiencies with both their recruitment process and their type rating course. Either that, or your anecdote is a little less truthful than you are letting on.