If you've been there 23 years then the leaving that comfy world of benefits; colleagues and comfortableness (despite the toxic atmosphere) may seem daunting and getting into the swing of the looking on the job market will seem daunting. But once you are selected, you don't get a lot of time - maybe a month in Europe; maybe a 1-2 days in the US.
I am afraid you are in a high risk zone now. If you are director level with 25+ yrs, then it would cost them too much in redundancy and likely to be harder to replace for continuity. Below Director then yes - get ready, I am afraid.
I would say, start looking anyway. You've got nothing to lose whilst you're in that comfort bubble.
It is easier to look for work whilst you are in work. Only because there is less pressure on you, as you have money coming in.
So at least update your CV. Don't use "What I did" statements or "my responsibilities are: Bullet, bullet, bullet nonsense, as that just screams "So what?". Instead, say what you achieved (Situation, task, Activity, Results) and get IT agencies on your side. Job sites are pubic and tend to attract too many after the same job. Agencies hear the jobs first, on company's own sites, that you won't necessarily find in searches. Use colleagues, friends and get your skills and profile updated in Linked-in. Loads of recruiters scan that for people with the skills they need and do read your summary to make sure. So be careful that your most relevant skills appear at the top of the list.
Above all - be clear about what you want. Don't use generic buzzwords; it tells employers nothing. Don't try and dither between roles that you could do at a push. All this transferable skills stuff is more difficult to sell when you're over 45 as your experience will need to be better than the next person who has thrived in that role in the past 10 yrs and has applied for the same job.
Be very specific and make every CV statement relevant to the Job spec exactly. Tell an employer that you meet their job spec with great examples. Then do your homework on their values and core vision and background before the interview.
I know its difficult after so many years, a lot of us were in the same boat. But once you join an employer that values its staff, allows you the freedom to manage and drive the business forward, it feels so much more invigorating and makes you feel younger! It's amazing just how demoralising DXC was and how it seemed to s--- the life force out of many of us until we made that transition. Yeah, sure some out of choice and some involuntary - but on the other side it does feel good :-)
Best of luck to you.