I'm not against spending money on essential tools of the trade that you keep for years but carrying around a super expensive laptop makes me feel really nervous e.g. it could get stolen, dropped, get wet in the rain, drinks spilt on it.
When I don't need the extra power, I think I'd rather travel with an easy to replace $900 laptop than a $3,000 one for ease of mind.
It's the opposite for me. I would use the €4000 HP ZBook from work on the subway or on the street. But I wouldn't use my €1000 mid-2015 MacBook Pro because I know I wouldn't be able to buy a new one if it got stolen or would break.
Money can't buy everything - if they don't make the 2015 chassis anymore (ie. no Touchbar, which some people still very much prefer), then you cant really get a replacement for it, no matter the price.
I've made a claim on a laptop before and it took a couple of weeks to get a replacement, plus claims make your premiums go up. I'm not saying it's not workable, but I feel more at ease carrying around less expensive equipment that's easier to replace.
When I don't need the extra power, I think I'd rather travel with an easy to replace $900 laptop than a $3,000 one for ease of mind.