Career Advice - Moving from (pre-)seed startups to one of the largest FS companies - I will not promote

Hey all, I dont know where to post this so please let me know if there is a better place. I am kinda lost and looking for advice/mental clarity i guess. I have always worked with really small startups <5 people. Now i have recently given the final interview with one of the largest FS companies in the world (10K+ emps) and I am having some second thoughts after the last interview. I am a builder through and through with a strong focus on AI. One of the things that got me feeling this way is during the last interview they shared that they have a strong culture of buying software rather than building. At startups - its all about saving money and releasing fast, I've built auth to save 70k a year and migrated from AWS to Azure cause we got some free credits. I custom built a eval lib so i wouldnt have to pay whatever they charge. I was also asked why i didnt use low-code/no-code workflow builders for any of my AI pipelines or agentic workflows. I didnt have an answer apart from I like building. I dont really know what is going through my head tbh. I've mostly been the one making the design decisions and only have my code reviewed when a major feature was being shipped. In the new role there is a hierarchy and I will definitely have a lot to learn. The caliber is quite good. I dont know why im feeling like this or even what i am feeling but I'd like to get a thrid person opinion. Feel free to poke and prod me. Ive just done a brain dump so sorry for the incoherence but i genuinely cant make sense of my thoughts. I think my main question is probably, is this change right for me? or am I hesitating cause i am nervous about something and dont know what it is. thanks for the long read - sorry for the lack of TLDR.