Questioning my decision to join startup

So I had an interview with this early early stage startup (2 founders mainly working on it with couple of contractors). They seem to be having traction. They described their product and tech. The founders had a previous successful exit and are bootstrapping this startup. I was a bit impressed but I was NOT completely decided if I wanted to join. Afterwards i asked about what compensation would look like. The said 160k plus equity. Which is a bit more than what I am making currently but not a huge. I had a 3 week vaca planned while all this was going on. So I told them that I needed time to think as this was going to be a big decision for me. I will get back to them after vaca. They said they really like me and they are ok waiting (what the recruiter told me). A week and half later, while still on vaca, the recruiter email asking if I made a decision. I thought about it more and replied I am in after 3 days. He then proceeded to call me to tell me that things have changed a bit. That they hired a developer manager who I will now have to interview with again and that the founders where having doubts. The recruiter Quote one of the founders “they don’t know if I will stick around if things become difficult or not easy”. I asked what “not easy” meant he mentioned something like difficulties with the technical side of development . I am currently an SMTS (senior member of technical staff ) or senior software Eng with 5 YOE. 150 TC I am now asking myself if it will be worth to pursue this. Your thoughts