This is a good question. One problem statement that I came up with among Central and Eastern European countries was related to the pre-conditions to implement industry 4.0. Certain countries like Hungary or Slovakia started to implement industry 4.0 on the small and medium scale without having the necessary preparation or domestic technological endowments. Just imagine the case that, because of rent-seeking and crony capitalism reasons, the government promotes industry 4.0 to channel FDI and related financial activities to boost industry 4.0 activities which contradict to the natural evolution of economic growth within a national economy. Moreover, political cycles favor national populism via industry 4.0 activities. Countries like the USA and Japan are still developing nanotechnologies and still, they have not finished the integration of new technologies like 3D printing; however, we observe CEE countries claiming substantial achievements. In my opinion, these are heavily related to political cycles. So, obviously, there are certain overlapping dynamics between business and political cycles that on SME level target industry 4.0. All of these are my personal observations. I totally accept if someone would not agree with me.
Costs of training the people, implementing the technology maybe even the robustness (or more like lack of it) in technology to be used in certain rough environemtns.
Availability of access to Internet and services.
Sustainability of using IoT technologies wireless ways (huge amount of batteries all around to support wireless operations).
and so on. Most of the problems related to using IoT and I4.0 everywhere are also present in developing countries too.
The major gap I have found in my research is the innovation gap. In spite of mindset and attitude Startups/SMEs unable to grow and scale-up due to the ecosystem issues and innovation in product, process and service. Another dimension is disruptive ideas under the industry 4.0 era of IoT, AI is a tool for creating competitive advantage. Another weak link is Big Data Analytics, where information is power. In developing the country's through education knowledge is imparted but failed to inculcate the practical orientation and problem-solving skills. Poor participation of women in the economic development process, where they are technically trained but not professionally involved in technology industries is another prong of this problem. My co-authored research paper on "SDG 9 Imperatives" may give you insight into the issues, especially developing nations context. Thank you!